diff --git a/compiler/src/capture/capture.ts b/compiler/src/capture/capture.ts
index 4b92679..010a2aa 100644
--- a/compiler/src/capture/capture.ts
+++ b/compiler/src/capture/capture.ts
@@ -14,6 +14,7 @@ import {
 import { discoverBreakpoints } from "./breakpoints.js";
 import { writeJSON, writeJSONCompact, writeBytes, ensureDir } from "../util/fsx.js";
 import { sha1_12, round } from "../util/canonical.js";
+import { isZipArchive, extractDotLottieJson } from "./dotlottie.js";
 
 export const REQUIRED_VIEWPORTS = [375, 768, 1280, 1920] as const;
 // The dense width set captured for SIZE INFERENCE: a node sampled at 9 widths reveals its sizing
@@ -115,13 +116,19 @@ export function isRetryableAssetFailure(type: string, status: number | null): bo
   return status >= 500 || status === 429;
 }
 
-function extFromUrl(url: string): string {
+// Bound on a preserved file extension. Real extensions are short, but a hard 5-char cap
+// silently truncates legitimate ones (`.lottie` → `.lotti`, `.webmanifest` → `.webma`),
+// which then mis-materializes the asset. Keep the guard generous enough for the longest
+// real extensions and reject anything absurdly long (a dotted path segment, not an ext).
+const MAX_EXT_LEN = 12;
+
+export function extFromUrl(url: string): string {
   try {
     const p = new URL(url).pathname;
     const dot = p.lastIndexOf(".");
     if (dot >= 0 && dot > p.lastIndexOf("/")) {
-      const ext = p.slice(dot + 1).toLowerCase().slice(0, 5);
-      if (/^[a-z0-9]+$/.test(ext)) return ext;
+      const ext = p.slice(dot + 1).toLowerCase();
+      if (ext.length <= MAX_EXT_LEN && /^[a-z0-9]+$/.test(ext)) return ext;
     }
   } catch { /* ignore */ }
   return "";
@@ -175,6 +182,83 @@ export function looksLikeVideoFile(bytes: Buffer): boolean {
   return false;
 }
 
+/** Container-magic check for accepted font bytes, mirroring `looksLikeVideoFile`. A router that
+ *  answers 200+HTML for an unknown `/media/*` path (common on SPA hosts) otherwise gets stored as
+ *  a `.woff2`; the browser rejects it as a font and the whole page falls through to a system
+ *  fallback. Accept only the real font-container signatures — woff2 (`wOF2`), woff (`wOFF`),
+ *  OpenType/CFF (`OTTO`), TrueType (`\x00\x01\x00\x00` or `true`/`ttcf`), and EOT (the version
+ *  header at bytes 8..11 is `\x01\x00\x01\x00`/`\x02\x00\x01\x00`, so key EOT off its unique
+ *  0x504C signature at offset 34) — and explicitly reject an HTML/text body. */
+export function looksLikeFontFile(bytes: Buffer): boolean {
+  if (bytes.length < 4) return false;
+  const b0 = bytes[0]!, b1 = bytes[1]!, b2 = bytes[2]!, b3 = bytes[3]!;
+  // A leading `<` (`<!DOCTYPE`, `<html`, `<?xml`, `<svg`) is never a binary font container.
+  if (b0 === 0x3c) return false;
+  const tag = bytes.subarray(0, 4).toString("latin1");
+  if (tag === "wOF2" || tag === "wOFF") return true; // woff2 / woff
+  if (tag === "OTTO" || tag === "true" || tag === "ttcf") return true; // CFF OpenType / TrueType / TrueType collection
+  if (b0 === 0x00 && b1 === 0x01 && b2 === 0x00 && b3 === 0x00) return true; // TrueType sfnt (\x00\x01\x00\x00)
+  // EOT: a little-endian byte count precedes a version/flags header; its stable marker is the
+  // 0x504C ("LP") magic at byte offset 34.
+  if (bytes.length >= 36 && bytes[34] === 0x4c && bytes[35] === 0x50) return true;
+  return false;
+}
+
+/**
+ * A `<source>` candidate for the HTML media resource-selection algorithm. `media`/`type` are the
+ * raw attribute strings (null/undefined when absent, matching a missing attribute).
+ */
+export interface VideoSourceCandidate {
+  media?: string | null;
+  type?: string | null;
+}
+
+/**
+ * Pure re-implementation of the source-selection step of the HTML media resource-selection
+ * algorithm: return the index of the FIRST `<source>` (document order) that is eligible NOW, or -1
+ * when none is. A source is eligible when its `media` query matches (a missing/empty media matches
+ * unconditionally) AND the UA can play its `type` (a missing/empty type is not a disqualifier —
+ * `canPlayType` is only consulted when a type is present).
+ *
+ * The predicates are injected so this is testable in Node (the in-page caller passes the real
+ * `matchMedia`/`canPlayType`). Kept deterministic: no state, first-match wins in document order.
+ */
+export function selectVideoSourceIndex(
+  sources: VideoSourceCandidate[],
+  mediaMatches: (media: string) => boolean,
+  canPlay: (type: string) => boolean,
+): number {
+  for (let i = 0; i < sources.length; i++) {
+    const s = sources[i]!;
+    const media = (s.media ?? "").trim();
+    if (media && !mediaMatches(media)) continue;
+    const type = (s.type ?? "").trim();
+    if (type && !canPlay(type)) continue;
+    return i;
+  }
+  return -1;
+}
+
+/**
+ * Pure decision for the per-video seek in normalizeVideoTime, extracted so the reloaded-set /
+ * seek-target branch is unit-testable in Node (the in-page loop applies the same rule to real
+ * elements). Returns the seek to perform after the re-selection reload pass, or null to fast-skip.
+ *
+ * - A `reloaded` video sits at t=0 with the HTML element's show-poster flag freshly set. Seeking to
+ *   0 would be a no-op that fires no `seeked` and leaves the poster showing, so force a genuine seek
+ *   to a tiny epsilon to clear the flag and paint the new source's frame 0.
+ * - A non-reloaded video already at t≈0 needs nothing (skip). Otherwise seek it back to 0.
+ */
+export function planVideoSeek(
+  reloaded: boolean,
+  currentTime: number,
+): { target: number } | null {
+  const EPSILON = 1e-4;
+  if (reloaded) return { target: EPSILON };
+  if (Math.abs(currentTime) < 1e-3) return null;
+  return { target: 0 };
+}
+
 async function autoScroll(page: import("playwright").Page, vpHeight: number): Promise<void> {
   // Scroll through the page to trigger lazy-loaded images/backgrounds, then return
   // to the top so document-coordinate bboxes are measured from a settled layout.
@@ -209,6 +293,41 @@ async function settle(page: import("playwright").Page, maxMs = 2500): Promise<vo
   await page.waitForTimeout(250);
 }
 
+/**
+ * Stage 2 — scroll-state reset immediately before a per-viewport snapshot. The motion /
+ * dwell-scroll / carousel / element-screenshot passes above all leave the page scrolled or
+ * mid-transition; scroll-linked styles (Webflow scroll-state transforms, position:sticky
+ * offsets) then get baked into the captured computed styles for THAT viewport only, so a
+ * scroll-driven translateY leaks into one band and cascades. Reset window + inner scrollers
+ * to the top, wait for scroll-linked effects to settle across a few rAF ticks plus a short
+ * quiescence window, THEN let the caller snapshot. Bounded and deterministic.
+ */
+async function settleScrollTopBeforeSnapshot(page: import("playwright").Page): Promise<void> {
+  try {
+    await Promise.race([
+      page.evaluate(async () => {
+        const raf = () => new Promise<void>((r) => requestAnimationFrame(() => r()));
+        const resetAll = () => {
+          window.scrollTo(0, 0);
+          for (const el of Array.from(document.querySelectorAll("*"))) {
+            if (el.scrollLeft) el.scrollLeft = 0;
+            if (el.scrollTop) el.scrollTop = 0;
+          }
+        };
+        resetAll();
+        // Let scroll-linked effects (scroll-state classes, sticky offsets, JS scroll handlers)
+        // recompute at scroll 0 over several frames, re-asserting the top position each tick in
+        // case a handler nudged it, then hold briefly for quiescence.
+        for (let i = 0; i < 6; i++) { await raf(); resetAll(); }
+        await new Promise<void>((r) => setTimeout(r, 120));
+        resetAll();
+        await raf();
+      }),
+      new Promise<void>((r) => setTimeout(r, 4000)),
+    ]);
+  } catch { /* ignore — a best-effort reset never blocks the snapshot */ }
+}
+
 export type DismissResult = { dismissed: string[]; overlaysRemaining: number; removed: number; blocking: boolean };
 
 /**
@@ -219,64 +338,102 @@ export type DismissResult = { dismissed: string[]; overlaysRemaining: number; re
  * Removal of a stuck overlay happens later (finalizeOverlays) AFTER a settle, so a
  * just-clicked dialog has time to close and unlock scrolling before we judge it.
  */
+/**
+ * In-page dismissal click pass (exported for fixture tests). Runs in ONE document — the main
+ * page OR a cross-origin frame (Attentive/Recart/Klaviyo creatives host their Decline/× inside
+ * an iframe, so the caller runs this in every `page.frames()`). Traverses open shadow roots
+ * (Recart mounts its popup in a shadow tree) when scanning both containers and buttons.
+ */
+export function clickDismissInPage(): string[] {
+  const dismissed: string[] = [];
+  // Deep collector across open shadow roots.
+  const deepEls = (root: ParentNode, sel: string): Element[] => {
+    const out: Element[] = [];
+    const walk = (r: ParentNode): void => {
+      let hits: Element[] = [];
+      try { hits = Array.from(r.querySelectorAll(sel)); } catch { /* invalid selector */ }
+      out.push(...hits);
+      for (const el of Array.from(r.querySelectorAll("*"))) {
+        const sr = (el as HTMLElement).shadowRoot;
+        if (sr) walk(sr);
+      }
+    };
+    walk(root);
+    return out;
+  };
+  const vis = (el: Element): boolean => {
+    const cs = getComputedStyle(el);
+    if (cs.display === "none" || cs.visibility === "hidden" || parseFloat(cs.opacity || "1") === 0) return false;
+    const r = (el as HTMLElement).getBoundingClientRect();
+    return r.width > 0 && r.height > 0;
+  };
+  const click = (el: Element): void => { try { (el as HTMLElement).click(); } catch { /* ignore */ } };
+
+  // 1) Known consent-framework / generic close affordances, in priority order.
+  const KNOWN = [
+    "#onetrust-accept-btn-handler", "#accept-recommended-btn-handler", ".onetrust-close-btn-handler",
+    "#CybotCookiebotDialogBodyLevelButtonLevelOptinAllowAll", "#CybotCookiebotDialogBodyButtonAccept",
+    "#truste-consent-button", ".osano-cm-accept-all", ".osano-cm-dialog__close",
+    "[data-testid='uc-accept-all-button']", "[data-testid='uc-deny-all-button']",
+    "#didomi-notice-agree-button", ".didomi-continue-without-agreeing",
+    ".qc-cmp2-summary-buttons button[mode='primary']", "button[aria-label='Consent']",
+    ".cc-allow", ".cookie-consent-accept", "#hs-eu-confirmation-button", "#gdpr-consent-tool-wrapper button",
+  ];
+  for (const sel of KNOWN) {
+    for (const el of deepEls(document, sel)) {
+      if (vis(el)) { click(el); dismissed.push(sel); break; }
+    }
+  }
+
+  // 2) Scoped text-button pass: only inside overlay-ish containers (dialogs, or id/class naming
+  //    cookie/consent/modal/popup/newsletter/overlay/ccpa/privacy) so we never click an ordinary
+  //    page button. ACCEPT now also covers email-capture DECLINE affordances ("decline",
+  //    "no thanks", "not now", …) — a popup's own opt-out is the surest deterministic close.
+  const ACCEPT = new Set([
+    "accept", "accept all", "accept all cookies", "accept cookies", "accept & close",
+    "i accept", "i agree", "agree", "agree and continue", "allow all", "allow cookies",
+    "allow all cookies", "got it", "ok", "okay", "continue", "no thanks", "no, thanks",
+    "dismiss", "close", "got it!", "understood", "yes, i agree",
+    "decline", "no, thank you", "not now", "maybe later", "no thank you", "skip", "reject all",
+  ]);
+  const containerSel =
+    "[role='dialog'],[aria-modal='true'],[id*='cookie' i],[class*='cookie' i],[id*='consent' i]," +
+    "[class*='consent' i],[class*='gdpr' i],[id*='gdpr' i],[class*='modal' i],[class*='popup' i]," +
+    "[class*='newsletter' i],[class*='interstitial' i],[class*='overlay' i],[id*='overlay' i]," +
+    "[class*='ccpa' i],[id*='ccpa' i],[class*='privacy' i],[id*='pop' i]";
+  const containers = deepEls(document, containerSel);
+  for (const c of containers) {
+    if (!vis(c)) continue;
+    // Text/value-matched accept/decline buttons.
+    const btns = deepEls(c, "button,[role='button'],a,input[type='button'],input[type='submit']");
+    let clicked = false;
+    for (const b of btns) {
+      const t = (b.textContent || (b as HTMLInputElement).value || "").replace(/\s+/g, " ").trim().toLowerCase();
+      if (t && ACCEPT.has(t) && vis(b)) { click(b); dismissed.push("text:" + t); clicked = true; break; }
+    }
+    if (clicked) continue;
+    // aria-label / title close affordance (icon-only ×, no text content to match).
+    const closers = deepEls(c, "[aria-label*='close' i],[aria-label*='dismiss' i],[title*='close' i],button.close,.close-button,[class*='close' i][role='button']");
+    for (const x of closers) {
+      if (vis(x)) { click(x); dismissed.push("close:" + ((x.getAttribute("aria-label") || x.getAttribute("title") || "x")).slice(0, 24)); break; }
+    }
+  }
+  return dismissed;
+}
+
 async function clickDismiss(page: import("playwright").Page): Promise<string[]> {
-  try {
-    return await Promise.race([
-      page.evaluate(() => {
-        const dismissed: string[] = [];
-        const vis = (el: Element): boolean => {
-          const cs = getComputedStyle(el);
-          if (cs.display === "none" || cs.visibility === "hidden" || parseFloat(cs.opacity || "1") === 0) return false;
-          const r = (el as HTMLElement).getBoundingClientRect();
-          return r.width > 0 && r.height > 0;
-        };
-        const click = (el: Element): void => { try { (el as HTMLElement).click(); } catch { /* ignore */ } };
-
-        // 1) Known consent-framework / generic close affordances, in priority order.
-        const KNOWN = [
-          "#onetrust-accept-btn-handler", "#accept-recommended-btn-handler", ".onetrust-close-btn-handler",
-          "#CybotCookiebotDialogBodyLevelButtonLevelOptinAllowAll", "#CybotCookiebotDialogBodyButtonAccept",
-          "#truste-consent-button", ".osano-cm-accept-all", ".osano-cm-dialog__close",
-          "[data-testid='uc-accept-all-button']", "[data-testid='uc-deny-all-button']",
-          "#didomi-notice-agree-button", ".didomi-continue-without-agreeing",
-          ".qc-cmp2-summary-buttons button[mode='primary']", "button[aria-label='Consent']",
-          ".cc-allow", ".cookie-consent-accept", "#hs-eu-confirmation-button", "#gdpr-consent-tool-wrapper button",
-        ];
-        for (const sel of KNOWN) {
-          try {
-            for (const el of Array.from(document.querySelectorAll(sel))) {
-              if (vis(el)) { click(el); dismissed.push(sel); break; }
-            }
-          } catch { /* invalid selector in this browser */ }
-        }
-
-        // 2) Scoped text-button pass: only inside overlay-ish containers (dialogs,
-        //    or id/class naming cookie/consent/modal/popup/newsletter) so we never
-        //    click an ordinary page button.
-        const ACCEPT = new Set([
-          "accept", "accept all", "accept all cookies", "accept cookies", "accept & close",
-          "i accept", "i agree", "agree", "agree and continue", "allow all", "allow cookies",
-          "allow all cookies", "got it", "ok", "okay", "continue", "no thanks", "no, thanks",
-          "dismiss", "close", "got it!", "understood", "yes, i agree",
-        ]);
-        const containerSel =
-          "[role='dialog'],[aria-modal='true'],[id*='cookie' i],[class*='cookie' i],[id*='consent' i]," +
-          "[class*='consent' i],[class*='gdpr' i],[id*='gdpr' i],[class*='modal' i],[class*='popup' i]," +
-          "[class*='newsletter' i],[class*='interstitial' i]";
-        let containers: Element[] = [];
-        try { containers = Array.from(document.querySelectorAll(containerSel)); } catch { /* ignore */ }
-        for (const c of containers) {
-          if (!vis(c)) continue;
-          const btns = Array.from(c.querySelectorAll("button,[role='button'],a,input[type='button'],input[type='submit']"));
-          for (const b of btns) {
-            const t = (b.textContent || (b as HTMLInputElement).value || "").replace(/\s+/g, " ").trim().toLowerCase();
-            if (t && ACCEPT.has(t) && vis(b)) { click(b); dismissed.push("text:" + t); break; }
-          }
-        }
-        return dismissed;
-      }),
+  // Run the click pass in the main document AND every frame — cross-origin popup creatives
+  // (Attentive/Recart/…) host their Decline/close controls inside an iframe that the top
+  // document cannot reach, but Playwright can evaluate inside each frame from Node.
+  const runOne = (frame: import("playwright").Frame): Promise<string[]> =>
+    Promise.race([
+      frame.evaluate(clickDismissInPage).catch(() => [] as string[]),
       new Promise<string[]>((res) => setTimeout(() => res([]), 6000)),
     ]);
+  try {
+    const frames = page.frames();
+    const results = await Promise.all(frames.map((f) => runOne(f).catch(() => [] as string[])));
+    return results.flat();
   } catch {
     return [];
   }
@@ -292,57 +449,168 @@ async function clickDismiss(page: import("playwright").Page): Promise<string[]>
  * sticky chrome is never stripped. Reports `blocking` = a scroll-locking overlay we
  * could not clear (the pollution gate keys off this, not mere overlay presence).
  */
-async function finalizeOverlays(page: import("playwright").Page): Promise<{ overlaysRemaining: number; removed: number; blocking: boolean; removedLabels: string[] }> {
+export type FinalizeOverlaysResult = { overlaysRemaining: number; removed: number; blocking: boolean; removedLabels: string[] };
+
+/**
+ * In-page overlay finalizer (exported so fixture tests can page.evaluate it directly).
+ * Detects any full-viewport, fixed/sticky BLOCKING layer still present and — when the page
+ * is scroll-locked (a state legit pages never enter) — removes it. Key robustness rules:
+ *
+ *  (a) EFFECTIVE z-index: an element with `z-index:auto` inherits its stacking position from
+ *      the nearest positioned/opacity/transform ancestor that establishes a stacking context.
+ *      A vendor popup iframe is z:auto but sits inside a z=INT_MAX wrapper, so per-element
+ *      `parseInt("auto")` under-reads it — resolve z through the ancestor chain instead.
+ *  (b) LOCK relaxes the z gate: on a scroll-locked page, ANY fixed/sticky full-viewport layer
+ *      is blocking regardless of z (catches a z:auto creative and a z=50 CCPA dialog). Off a
+ *      locked page we keep the z>=100 floor to avoid stripping legit fixed content.
+ *  (c) OVERLAY UNIT: a 0-size (height:0) max-z wrapper whose descendant is a full-viewport
+ *      fixed iframe is ONE overlay — the wrapper carries the z, the iframe carries the pixels.
+ *      Detecting either means removing BOTH (climb from a removable iframe to its high-z
+ *      wrapper ancestor; and treat a max-z 0-size wrapper as an overlay via its full-viewport
+ *      descendant). Neither alone passes the area+z gate, so they must be grouped.
+ *  (d) LOUD FAILURE: if the lock persists after removal (or was locked with nothing detected),
+ *      report blocking=true so the pollution gate fails rather than shipping a polluted capture.
+ */
+export function finalizeOverlaysInPage(): FinalizeOverlaysResult {
+  const vw = window.innerWidth, vh = window.innerHeight;
+  // Deep element walk that descends into OPEN shadow roots. A shadow host reports 0 light-DOM
+  // children, so a popup mounted inside a shadow tree (Recart's `#recart-popup-root`) is invisible
+  // to a plain `querySelectorAll("*")` — its full-viewport fixed layer would never be detected and
+  // would paint into every screenshot. Traverse `element.shadowRoot` (open only; closed roots are
+  // unreachable — the host itself is still caught by the geometry gate below and removed whole).
+  const deepEls = (root: ParentNode): Element[] => {
+    const out: Element[] = [];
+    const push = (r: ParentNode): void => {
+      for (const el of Array.from(r.querySelectorAll("*"))) {
+        out.push(el);
+        const sr = (el as HTMLElement).shadowRoot;
+        if (sr) push(sr);
+      }
+    };
+    push(root);
+    return out;
+  };
+  const isLocked = (): boolean => {
+    const b = document.body, h = document.documentElement;
+    const bs = getComputedStyle(b), hs = getComputedStyle(h);
+    return bs.overflow === "hidden" || hs.overflow === "hidden" ||
+      bs.overflowY === "hidden" || hs.overflowY === "hidden" ||
+      bs.position === "fixed" || bs.position === "absolute";
+  };
+  // Effective z-index: climb to the nearest ancestor that both is positioned/creates a stacking
+  // context AND reports a numeric z-index. `z-index:auto` on a positioned child paints in its
+  // parent stacking context, so the parent's z is the layer's true stacking rank.
+  const effectiveZ = (el: Element): number => {
+    let cur: Element | null = el;
+    let hops = 0;
+    while (cur && hops < 20) {
+      const cs = getComputedStyle(cur);
+      const zi = parseInt(cs.zIndex || "", 10);
+      const positioned = cs.position !== "static";
+      if (Number.isFinite(zi) && positioned) return zi;
+      cur = cur.parentElement;
+      hops++;
+    }
+    return 0;
+  };
+  const rectOf = (el: Element) => (el as HTMLElement).getBoundingClientRect();
+  const fullViewport = (r: DOMRect): boolean => r.width >= vw * 0.7 && r.height >= vh * 0.5 && (r.width * r.height) / (vw * vh) >= 0.5;
+  const painting = (cs: CSSStyleDeclaration): boolean =>
+    cs.display !== "none" && cs.visibility !== "hidden" && parseFloat(cs.opacity || "1") !== 0;
+
+  const locked = isLocked();
+
+  // Candidate blocking layers. A layer qualifies when it is fixed/sticky, painting, and either
+  // (1) itself full-viewport, or (2) a 0-size/high-z wrapper whose descendant is full-viewport
+  // (the overlay-unit case — the wrapper holds the z, an inner iframe holds the pixels).
+  // Full-viewport descendant test that pierces shadow roots (Recart mounts the covering layer
+  // inside the host's shadow tree, so a light-DOM `querySelectorAll` would find nothing).
+  const hasFullDescendant = (el: Element): boolean => {
+    const scope: ParentNode = (el as HTMLElement).shadowRoot ?? el;
+    return deepEls(scope).some((d) => { const dcs = getComputedStyle(d); return painting(dcs) && (dcs.position === "fixed" || dcs.position === "sticky" || dcs.position === "absolute") && fullViewport(rectOf(d)); });
+  };
+  const bigOverlays = (): HTMLElement[] => {
+    const out: HTMLElement[] = [];
+    for (const el of deepEls(document.body)) {
+      const cs = getComputedStyle(el);
+      const isShadowHost = !!(el as HTMLElement).shadowRoot;
+      // A shadow host is usually position:static with a fixed layer INSIDE its root; still test it
+      // (via its shadow descendants) so the whole host can be removed as one overlay unit.
+      if (cs.position !== "fixed" && cs.position !== "sticky" && !isShadowHost) continue;
+      if (!painting(cs)) continue;
+      const r = rectOf(el);
+      const z = effectiveZ(el);
+      // Off a locked page keep the z>=100 floor; on a locked page any full-viewport fixed
+      // layer is blocking (rule b). A max-z wrapper is a blocking layer even at 0 size when it
+      // wraps a full-viewport descendant (rule c) — legit chrome never reaches the INT_MAX band.
+      const positioned = cs.position === "fixed" || cs.position === "sticky";
+      const selfFull = positioned && fullViewport(r);
+      const wrapsFull = (isShadowHost || r.width < 4 || r.height < 4) && (isShadowHost || z >= 100) && hasFullDescendant(el);
+      if (!selfFull && !wrapsFull) continue;
+      const zPass = locked || z >= 100 || (wrapsFull && isShadowHost);
+      if (zPass) out.push(el as HTMLElement);
+    }
+    // Keep outermost only (a wrapper subsumes its inner full-viewport iframe — the overlay unit).
+    // `Node.contains` does NOT cross shadow boundaries, so also treat a candidate that lives inside
+    // another candidate's shadow tree as contained — otherwise a shadow host AND its inner layer
+    // both survive and we double-remove (or leave the inner layer behind).
+    const shadowContains = (host: Element, node: Element): boolean => {
+      let cur: Node | null = node;
+      while (cur) {
+        const rootNode = cur.getRootNode();
+        if (rootNode instanceof ShadowRoot) {
+          if (rootNode.host === host || host.contains(rootNode.host)) return true;
+          cur = rootNode.host;
+        } else break;
+      }
+      return false;
+    };
+    return out.filter((el) => !out.some((o) => o !== el && (o.contains(el) || shadowContains(o, el))));
+  };
+
+  // A scroll-locked page behind a full-viewport overlay IS a blocking modal by definition
+  // (legit pages don't scroll-lock). Remove ANY such overlay that isn't page chrome — many
+  // modals/drawers carry no consent/modal keyword and an icon-only close, so a keyword/aria
+  // allowlist misses them. PROTECTED guards real chrome (header/nav/footer) only.
+  const PROTECTED = /header|navbar|nav-|site-nav|topbar|masthead|footer/i;
+  const sig = (el: HTMLElement): string => `${el.id} ${el.className}`.toString();
+
+  const removedLabels: string[] = [];
+  let removed = 0;
+  let remaining = bigOverlays();
+  if (remaining.length && locked) {
+    for (const el of remaining) {
+      const s = sig(el);
+      const z = effectiveZ(el);
+      // Scroll-locked + full-viewport ⇒ blocking modal; remove unless it's page chrome. Always
+      // remove iframes (cross-origin close, unclickable), max-z wrappers, and the overlay unit:
+      // when the layer IS or CONTAINS a full-viewport fixed iframe, remove the whole subtree
+      // (rule c — the 0-size wrapper + its iframe come out together as one node).
+      const isShadowHost = !!(el as HTMLElement).shadowRoot;
+      const containsIframe = el.tagName === "IFRAME" || !!el.querySelector("iframe") ||
+        (isShadowHost && !!(el as HTMLElement).shadowRoot!.querySelector("iframe"));
+      const removable = !PROTECTED.test(s) || el.getAttribute("aria-modal") === "true" ||
+        containsIframe || isShadowHost || z >= 100;
+      if (removable) { el.remove(); removed++; removedLabels.push((el.id || el.className || el.tagName).toString().slice(0, 40)); }
+    }
+    if (removed) {
+      document.body.style.overflow = "visible"; document.documentElement.style.overflow = "visible";
+      document.body.style.overflowY = "visible"; document.documentElement.style.overflowY = "visible";
+      document.body.style.position = "static";
+    }
+    remaining = bigOverlays();
+  }
+  // Loud failure (rule d): a persisting lock is blocking whether or not a specific overlay was
+  // still detectable — a scroll-locked capture is polluted, so surface it to the pollution gate.
+  const stillLocked = isLocked();
+  return { overlaysRemaining: remaining.length, removed, blocking: stillLocked && (remaining.length > 0 || locked), removedLabels };
+}
+
+async function finalizeOverlays(page: import("playwright").Page): Promise<FinalizeOverlaysResult> {
   try {
     return await Promise.race([
-      page.evaluate(() => {
-        const vw = window.innerWidth, vh = window.innerHeight;
-        const bigOverlays = (): HTMLElement[] => {
-          const out: HTMLElement[] = [];
-          for (const el of Array.from(document.body.querySelectorAll("*"))) {
-            const cs = getComputedStyle(el);
-            if (cs.position !== "fixed" && cs.position !== "sticky") continue;
-            if (cs.display === "none" || cs.visibility === "hidden" || parseFloat(cs.opacity || "1") === 0) continue;
-            const r = (el as HTMLElement).getBoundingClientRect();
-            const z = parseInt(cs.zIndex || "0", 10) || 0;
-            const area = (r.width * r.height) / (vw * vh);
-            if (area >= 0.5 && z >= 100 && r.width >= vw * 0.7 && r.height >= vh * 0.5) out.push(el as HTMLElement);
-          }
-          return out.filter((el) => !out.some((o) => o !== el && o.contains(el)));
-        };
-        const isLocked = (): boolean => {
-          const b = document.body, h = document.documentElement;
-          return getComputedStyle(b).overflow === "hidden" || getComputedStyle(h).overflow === "hidden" ||
-            getComputedStyle(b).position === "fixed";
-        };
-        // A scroll-locked page behind a full-viewport overlay IS a blocking modal by
-        // definition (legit pages don't scroll-lock). So remove ANY such overlay that
-        // isn't page chrome — many modals/drawers carry no consent/modal keyword and
-        // an icon-only close, so a keyword/aria allowlist misses them (ruggable's
-        // z-[1001] drawer). PROTECTED guards real chrome (header/nav/footer) only.
-        const PROTECTED = /header|navbar|nav-|site-nav|topbar|masthead|footer/i;
-        const sig = (el: HTMLElement): string => `${el.id} ${el.className}`.toString();
-
-        const removedLabels: string[] = [];
-        let removed = 0;
-        let remaining = bigOverlays();
-        if (remaining.length && isLocked()) {
-          for (const el of remaining) {
-            const s = sig(el);
-            const z = parseInt(getComputedStyle(el).zIndex || "0", 10) || 0;
-            // Scroll-locked + full-viewport ⇒ blocking modal; remove unless it's page
-            // chrome. Always remove iframes (cross-origin close, unclickable) and the
-            // max-z-index popup trick.
-            const removable = !PROTECTED.test(s) || el.getAttribute("aria-modal") === "true" ||
-              el.tagName === "IFRAME" || z >= 2_000_000_000;
-            if (removable) { el.remove(); removed++; removedLabels.push((el.id || el.className || el.tagName).toString().slice(0, 40)); }
-          }
-          if (removed) { document.body.style.overflow = "visible"; document.documentElement.style.overflow = "visible"; document.body.style.position = "static"; }
-          remaining = bigOverlays();
-        }
-        return { overlaysRemaining: remaining.length, removed, blocking: remaining.length > 0 && isLocked(), removedLabels };
-      }),
-      new Promise<{ overlaysRemaining: number; removed: number; blocking: boolean; removedLabels: string[] }>((res) => setTimeout(() => res({ overlaysRemaining: 0, removed: 0, blocking: false, removedLabels: [] }), 6000)),
+      page.evaluate(finalizeOverlaysInPage),
+      new Promise<FinalizeOverlaysResult>((res) => setTimeout(() => res({ overlaysRemaining: 0, removed: 0, blocking: false, removedLabels: [] }), 6000)),
     ]);
   } catch {
     return { overlaysRemaining: 0, removed: 0, blocking: false, removedLabels: [] };
@@ -475,10 +743,102 @@ async function captureVideoStills(page: import("playwright").Page): Promise<Vide
 }
 
 /**
- * Full-page screenshot with robustness for heavy/animated pages. The default 30s
- * timeout is exceeded by tall SaaS pages (Playwright also waits for web fonts);
- * use a long timeout, freeze animations (also improves determinism), and retry.
- * As a last resort take a viewport-only shot so the file exists (the capture gate
+ * Stage 2 — canvas raster fallback. A visible <canvas> (animated background, chart,
+ * WebGL scene) is a runtime-drawn surface the clone cannot reproduce as DOM, so it
+ * would render as an empty box. Rasterize each meaningful canvas to a PNG still under
+ * a synthetic URL (the normal asset pipeline rewrites it to a local file); the node is
+ * then marked with a `src` attr so generation emits the still as an <img> filling the
+ * canvas's box. `toDataURL` is exact but THROWS for tainted canvases and for WebGL
+ * contexts without preserveDrawingBuffer — those return a shot plan for the node-side
+ * element-screenshot fallback (composited pixels, works regardless). A WebGL canvas may
+ * also toDataURL to a blank image when the drawing buffer was already presented; that
+ * blank is accepted as-is (detecting blankness would be heuristic, not deterministic).
+ * The in-page part is exported for the fixture tests (page.evaluate'd directly).
+ */
+export type CanvasStillPlan = { stills: Array<{ url: string; dataUrl: string; sel: string }>; shots: Array<{ url: string; sel: string }> };
+export function captureCanvasStillsInPage(): CanvasStillPlan {
+  const stills: CanvasStillPlan["stills"] = [];
+  const shots: CanvasStillPlan["shots"] = [];
+  const hash = (s: string): string => { let h = 5381; for (let i = 0; i < s.length; i++) h = ((h << 5) + h + s.charCodeAt(i)) >>> 0; return h.toString(36); };
+  const canvases = Array.from(document.querySelectorAll("canvas"));
+  let i = 0;
+  for (const c of canvases) {
+    const r = c.getBoundingClientRect();
+    if (r.width < 48 || r.height < 48) continue; // not a meaningful painted surface
+    const cs = getComputedStyle(c);
+    if (cs.display === "none" || cs.visibility === "hidden" || parseFloat(cs.opacity || "1") < 0.05) continue;
+    const idx = i++;
+    c.setAttribute("data-clone-canvas", String(idx));
+    const sel = `canvas[data-clone-canvas="${idx}"]`;
+    const url = `https://clone-canvas.local/${idx}-${hash(c.id + "|" + c.width + "|" + c.height + "|" + idx)}.png`;
+    let ok = false;
+    try {
+      const dataUrl = c.toDataURL("image/png"); // throws if tainted / WebGL buffer unreadable
+      if (dataUrl.startsWith("data:image/png")) { stills.push({ url, dataUrl, sel }); ok = true; }
+    } catch { /* fall through to the element-screenshot plan */ }
+    if (!ok) shots.push({ url, sel });
+  }
+  return { stills, shots };
+}
+
+async function captureCanvasStills(page: import("playwright").Page): Promise<CanvasStillPlan> {
+  try {
+    return await Promise.race([
+      page.evaluate(captureCanvasStillsInPage),
+      new Promise<CanvasStillPlan>((res) => setTimeout(() => res({ stills: [], shots: [] }), 12_000)),
+    ]);
+  } catch {
+    return { stills: [], shots: [] };
+  }
+}
+
+// Chromium refuses/truncates screenshots past a texture-size cap; keep clip dimensions
+// under a conservative bound so captureFullPageViaCDP fails cleanly (→ Playwright fallback)
+// instead of returning a truncated image on pathologically tall pages.
+const CDP_MAX_SHOT_DIMENSION = 16_384;
+
+/**
+ * Full-page screenshot via CDP `Page.captureScreenshot` with `captureBeyondViewport:true`.
+ * Unlike Playwright's `fullPage:true` (which scroll-stitches — scrolling the page to render
+ * each band, FIRING scroll events that drive scroll-linked animations, e.g. IX2 grow-on-scroll
+ * or WAAPI scroll-timelines), CDP renders the whole page in ONE shot WITHOUT scrolling and
+ * never fires scroll events. So the resulting still is the genuine at-rest (unscrolled) page,
+ * matching the DOM snapshot the walk grades. Writes a PNG to `path`. Throws on any failure so
+ * the caller can fall back to the Playwright path.
+ */
+export async function captureFullPageViaCDP(page: import("playwright").Page, path: string): Promise<void> {
+  const client = await page.context().newCDPSession(page);
+  try {
+    const metrics = await client.send("Page.getLayoutMetrics") as {
+      cssContentSize?: { width: number; height: number };
+      contentSize?: { width: number; height: number };
+    };
+    const size = metrics.cssContentSize ?? metrics.contentSize;
+    if (!size || !(size.width > 0) || !(size.height > 0)) throw new Error("cdp: empty content size");
+    const width = Math.ceil(size.width);
+    const height = Math.ceil(size.height);
+    if (width > CDP_MAX_SHOT_DIMENSION || height > CDP_MAX_SHOT_DIMENSION) {
+      throw new Error(`cdp: content ${width}x${height} exceeds max shot dimension`);
+    }
+    const shot = await client.send("Page.captureScreenshot", {
+      format: "png",
+      captureBeyondViewport: true,
+      clip: { x: 0, y: 0, width, height, scale: 1 },
+    }) as { data: string };
+    if (!shot?.data) throw new Error("cdp: no screenshot data");
+    writeBytes(path, Buffer.from(shot.data, "base64"));
+  } finally {
+    await client.detach().catch(() => { /* ignore */ });
+  }
+}
+
+/**
+ * Full-page screenshot with robustness for heavy/animated pages. Prefers CDP capture
+ * (captureFullPageViaCDP — no scroll-stitch, so scroll-linked animations aren't scrubbed
+ * and the still is the true at-rest page). On ANY CDP failure, falls back to Playwright's
+ * `fullPage:true` (which scroll-stitches but freezes animations); the default 30s timeout
+ * is exceeded by tall pages (Playwright also waits for web fonts), so use a long timeout and
+ * retry. As a last resort take a viewport-only shot so the file exists (the capture gate
  * checks presence; a partial image still beats none).
  */
 async function captureScreenshot(
@@ -487,6 +847,13 @@ async function captureScreenshot(
   vw: number,
   log: (e: Record<string, unknown>) => void,
 ): Promise<void> {
+  try {
+    await captureFullPageViaCDP(page, path);
+    log({ event: "screenshot_cdp", viewport: vw });
+    return;
+  } catch (eCdp) {
+    log({ event: "screenshot_cdp_fallback", viewport: vw, error: String(eCdp).slice(0, 200) });
+  }
   for (let attempt = 0; attempt < 2; attempt++) {
     try {
       await page.screenshot({ path, fullPage: true, timeout: 90_000, animations: "disabled" });
@@ -505,6 +872,131 @@ async function captureScreenshot(
   }
 }
 
+/**
+ * Pause every <video> and seek it to time 0, then wait for that seek to actually PAINT, so a
+ * screenshot taken right after is deterministic. A video's playback time is runtime state: a one-shot
+ * animation ends on its last frame, an autoplaying loop sits at an arbitrary offset, and the time a
+ * given viewport's shot happens to catch is nondeterministic. Without normalization the SOURCE and the
+ * (frame-0, non-playing) CLONE can show different frames of the same element — a phantom perceptual
+ * diff that no CSS change can close. Seeking BOTH sides to frame 0 before EVERY viewport screenshot
+ * removes it. `seeked` fires once the new frame is decoded; we still yield two rAFs so the compositor
+ * has painted it before the screenshot reads pixels. Bounded so a stalled/unseekable video can't hang.
+ *
+ * FIRST it re-runs `<source media>` resource selection for THIS viewport. The capture pipeline loads
+ * the page once at the canonical width and reaches every other viewport by resizing — but the HTML
+ * media resource-selection algorithm evaluates `<source media>` only at load, so an aspect/orientation
+ * -gated hero video stays frozen on whatever variant matched at load width across all resized shots.
+ * The validator fresh-loads per viewport and correctly re-selects, so the two channels disagree on
+ * which variant is on screen (a large phantom diff on full-bleed portrait/landscape hero videos).
+ * Re-selecting here keeps the channels symmetric; it is a no-op on the fresh-loading validator side
+ * and — the common case — a no-op whenever the current selection is still the right one, so the fast
+ * path never touches `video.load()`.
+ */
+export async function normalizeVideoTime(
+  page: import("playwright").Page,
+  log?: (event: Record<string, unknown>) => void,
+): Promise<void> {
+  try {
+    const reselections = await page.evaluate(async () => {
+      const vids = Array.from(document.querySelectorAll("video"));
+      const raf = () => new Promise<void>((r) => requestAnimationFrame(() => r()));
+
+      // Re-select the <source> the resource-selection algorithm would pick at the CURRENT viewport,
+      // mirroring selectVideoSourceIndex (Node-side, unit-tested): first source in document order
+      // whose media matches (missing media matches unconditionally) and whose type is playable
+      // (missing type is never disqualifying). Only reload when the winner differs from what is
+      // currently loaded — the fast path leaves untouched videos alone.
+      //
+      // Track which videos we reloaded. A reload resets the element's *show-poster flag* to true and
+      // sets currentTime to 0; the follow-up pause() cancels the pending autoplay, so the one thing
+      // that would have cleared that flag (playback beginning) never happens. Left uncleared, the
+      // element renders its `poster` image — which for an aspect-gated hero is a frame of the WRONG
+      // variant — instead of the freshly-selected source's frame 0. A real seek is the other
+      // flag-clearing path, but the fast-skip below bails at t=0. So force a genuine seek (to a tiny
+      // epsilon, not to the already-current 0) on exactly the reloaded videos to clear the flag and
+      // present the new source's decoded frame. Non-reloaded videos keep the existing fast skip.
+      const reloaded = new WeakSet<HTMLVideoElement>();
+      const reselections: { from: string; to: string; readyState: number }[] = [];
+      const reloadWaits: Promise<void>[] = [];
+      for (const v of vids) {
+        try {
+          const sources = Array.from(v.querySelectorAll("source"));
+          if (sources.length === 0) continue; // src attribute (no <source> children): nothing to re-select
+          let winner: HTMLSourceElement | null = null;
+          for (const s of sources) {
+            const media = (s.getAttribute("media") ?? "").trim();
+            if (media && !window.matchMedia(media).matches) continue;
+            const type = (s.getAttribute("type") ?? "").trim();
+            if (type && !v.canPlayType(type)) continue;
+            winner = s;
+            break;
+          }
+          if (!winner || !winner.src) continue;
+          // Compare resolved URLs; currentSrc is absolute, winner.src is already resolved.
+          if (v.currentSrc === winner.src) continue; // no change — fast path, do not reload
+          const from = v.currentSrc;
+          const to = winner.src;
+          v.load();
+          reloaded.add(v);
+          reloadWaits.push(new Promise<void>((resolve) => {
+            let settled = false;
+            const done = () => {
+              if (settled) return;
+              settled = true;
+              v.removeEventListener("loadeddata", done);
+              v.removeEventListener("seeked", done);
+              reselections.push({ from, to, readyState: v.readyState });
+              resolve();
+            };
+            if (v.readyState >= 2 /* HAVE_CURRENT_DATA */) { done(); return; }
+            // A post-reload `seeked` implies a decoded frame is ready too, so treat it as an
+            // additional readiness signal: on slow CDNs the epsilon seek (below) can land its
+            // `seeked` before `loadeddata`, which unblocks the FIRST viewport instead of waiting
+            // out the 4s bound and shooting the poster.
+            v.addEventListener("loadeddata", done, { once: true });
+            v.addEventListener("seeked", done, { once: true });
+            setTimeout(done, 4000); // bound: a stalled reload resolves anyway so the shot never hangs
+          }));
+        } catch { /* a malformed <source>/media query must not block the others */ }
+      }
+
+      const waits: Promise<void>[] = [];
+      const seekTo = (v: HTMLVideoElement, t: number) =>
+        new Promise<void>((resolve) => {
+          let settled = false;
+          const done = () => { if (settled) return; settled = true; v.removeEventListener("seeked", done); resolve(); };
+          v.addEventListener("seeked", done, { once: true });
+          try { v.currentTime = t; } catch { done(); }
+          setTimeout(done, 400); // bound: a stalled/unseekable video resolves anyway
+        });
+      for (const v of vids) {
+        try { v.pause(); } catch { /* ignore */ }
+        if (reloaded.has(v)) {
+          // A just-reloaded video sits at t=0 with the show-poster flag set. Seek to a tiny epsilon
+          // (not 0, which is already the current time and would fire no `seeked`) to force a genuine
+          // seek: it clears the flag and paints the new source's frame 0. Start it eagerly so its
+          // `seeked` can also satisfy the reload wait above on slow networks.
+          waits.push(seekTo(v, 1e-4));
+          continue;
+        }
+        // Seek to 0 only when not already there (a fresh seek to the current time may not fire `seeked`).
+        if (Math.abs(v.currentTime) < 1e-3) continue;
+        waits.push(seekTo(v, 0));
+      }
+      // Await the reload settles and the seeks together; the reload wait can be released by an
+      // epsilon seek's `seeked`, so both sets must be in flight before we block on either.
+      await Promise.all([...reloadWaits, ...waits]);
+      await raf(); await raf(); // let the decoded frame composite before the screenshot reads pixels
+      return reselections;
+    });
+    if (log && reselections && reselections.length) {
+      for (const r of reselections) {
+        log({ event: "video_source_reselected", from: r.from, to: r.to, readyState: r.readyState });
+      }
+    }
+  } catch { /* a page with no videos / an eval hiccup must never block the screenshot */ }
+}
+
 export async function captureSite(opts: {
   url: string;
   outDir: string; // source/ directory
@@ -577,9 +1069,24 @@ export async function captureSite(opts: {
     // page stored under first-stored-wins ships a corrupt file). Left unstored, the
     // asset surfaces in visual_assets_missing instead.
     if (type === "video" && !looksLikeVideoFile(bytes)) return;
+    // Same guard for fonts: a 200+HTML body (SPA router answering an unknown /media/* path) must not
+    // be stored as a .woff2. Left unstored, the face surfaces as failed, so the font graph can fall
+    // back to a correctly-resolved duplicate url instead of shipping an impostor the browser rejects.
+    if (type === "font" && !looksLikeFontFile(bytes)) return;
     const a = assetMap.get(url) ?? recordAsset(url, type, null, null, "network");
     if (a.storedAs) return;
-    const ext = extFromUrl(url) || extFromContentType(a.contentType) ||
+    // A `.lottie` (dotLottie) asset is a ZIP archive, not bare lottie-web JSON. lottie-web's
+    // `path:` loader does a JSON.parse and throws on the ZIP bytes, blanking the container. So
+    // unwrap it here: extract the default animation JSON and store THAT, materializing every
+    // lottie source as plain JSON regardless of the container it arrived in.
+    let extOverride: string | null = null;
+    if (type === "lottie" && isZipArchive(bytes)) {
+      const json = extractDotLottieJson(bytes);
+      if (!json) return; // unreadable dotLottie — leave unstored rather than ship a broken ZIP
+      bytes = json;
+      extOverride = "json";
+    }
+    const ext = extOverride || extFromUrl(url) || extFromContentType(a.contentType) ||
       (type === "css" ? "css" : type === "font" ? "woff2" : type === "svg" ? "svg" :
        type === "video" ? "mp4" : type === "lottie" ? "json" : "png");
     const name = `${sha1_12(url)}.${ext}`;
@@ -870,6 +1377,47 @@ export async function captureSite(opts: {
           await page.evaluate(() => window.scrollTo(0, 0));
           await page.waitForTimeout(80);
         }
+
+        // Stage 2: canvas raster fallback — same synthetic-URL mechanism as the video
+        // stills above (captureCanvasStills). Bytes ride the normal asset pipeline; the
+        // canvas node gets a `src` attr (whitelisted → survives the IR) that generation
+        // reads to emit the still as an <img> carrying the canvas's cid/box. The attr is
+        // stamped only AFTER bytes are stored, so a failed capture leaves the canvas
+        // rendering as an empty box, same as before.
+        const cplan = await captureCanvasStills(page);
+        const stampCanvasSrc = (sel: string, u: string): Promise<void> =>
+          page.evaluate(({ s, u: uu }) => { document.querySelector(s)?.setAttribute("src", uu); }, { s: sel, u }).catch(() => { /* ignore */ });
+        for (const s of cplan.stills) {
+          const comma = s.dataUrl.indexOf(",");
+          if (comma < 0) continue;
+          try {
+            const buf = Buffer.from(s.dataUrl.slice(comma + 1), "base64");
+            recordAsset(s.url, "image", "image/png", 200, "canvas-still");
+            storeBytes(s.url, "image", buf);
+            await stampCanvasSrc(s.sel, s.url);
+            log({ event: "canvas_still", viewport: vw, sel: s.sel });
+          } catch { /* ignore */ }
+        }
+        for (const s of cplan.shots) {
+          // Same reveal discipline as the video shots: a hidden canvas (entrance
+          // animation not yet fired) would time out locator.screenshot's visibility wait.
+          try {
+            await page.evaluate(forceRevealForShot, s.sel);
+            const buf = await page.locator(s.sel).first().screenshot({ type: "png", timeout: 5000, animations: "disabled" });
+            recordAsset(s.url, "image", "image/png", 200, "canvas-still");
+            storeBytes(s.url, "image", buf);
+            await stampCanvasSrc(s.sel, s.url);
+            log({ event: "canvas_still", viewport: vw, sel: s.sel });
+          } catch (e) {
+            log({ event: "canvas_still_error", viewport: vw, sel: s.sel, error: String(e).slice(0, 200) });
+          } finally {
+            await page.evaluate(restoreRevealForShot).catch(() => { /* ignore */ });
+          }
+        }
+        if (cplan.shots.length) {
+          await page.evaluate(() => window.scrollTo(0, 0));
+          await page.waitForTimeout(80);
+        }
       }
 
       // Stage 4/5: stamp capture-ids before the canonical snapshot so the IR carries
@@ -973,6 +1521,21 @@ export async function captureSite(opts: {
       const scrollAnimsCanceled = await neutralizeScrollTimelineAnimations(page);
       if (scrollAnimsCanceled) log({ event: "scroll_timeline_anims_canceled", viewport: vw, count: scrollAnimsCanceled });
 
+      // Final scroll-state reset immediately before the walk: every preceding pass (dwell
+      // scroll, carousel settle, element screenshots) can leave the page scrolled, which bakes
+      // scroll-linked transforms/offsets into this viewport's computed styles. Scroll to top and
+      // let scroll-linked effects settle so the snapshot records the genuine at-rest values.
+      await settleScrollTopBeforeSnapshot(page);
+
+      // Late-mounting dialogs (a CCPA opt-out that opens between the canonical and last
+      // viewport; a Recart/Attentive promo that fires on a timer) mount AFTER the load /
+      // post-scroll passes and would otherwise pollute this viewport's DOM snapshot. Re-run
+      // the dismissal pass immediately before the walk. Cheap when nothing matches — the
+      // settle only runs when a control was actually clicked or an overlay removed.
+      await applyDismiss("pre-snapshot");
+      dismissUnion.overlaysRemaining = Math.max(dismissUnion.overlaysRemaining, overlaysRemaining);
+      dismissUnion.blocking = dismissUnion.blocking || blocking;
+
       // Bound the in-page DOM walk: page.evaluate has no default timeout, so a
       // pathologically large/animated DOM (e.g. asana.com) could hang forever.
       const snapshot: PageSnapshot = await Promise.race([
@@ -1020,7 +1583,20 @@ export async function captureSite(opts: {
 
       // Persist DOM snapshot, and (unless skipped for a production clone) the full-page screenshot.
       writeJSONCompact(join(captureDir, `dom-${vw}.json`), snapshot);
-      if (opts.screenshots !== false) await captureScreenshot(page, join(screenshotsDir, `${vw}.png`), vw, log);
+      if (opts.screenshots !== false) {
+        // A promo popup can mount in the window between the DOM walk and the screenshot (Recart
+        // fires into a shadow root on a short timer). The screenshot is the ground-truth channel
+        // the perceptual gate compares against, so re-run dismissal right before it — otherwise a
+        // late popup paints over every shot even though the DOM snapshot came out clean. Cheap
+        // when nothing matches.
+        await applyDismiss("pre-screenshot");
+        dismissUnion.blocking = dismissUnion.blocking || blocking;
+        // Normalize every video to frame 0 (paused) at THIS viewport before the shot — the clone is
+        // always at frame 0, so pinning the source there too makes the two channels comparable
+        // regardless of the playback time the viewport happened to catch.
+        await normalizeVideoTime(page, log);
+        await captureScreenshot(page, join(screenshotsDir, `${vw}.png`), vw, log);
+      }
 
       // Stage 4: drive recognized affordances at the canonical viewport (opt-in).
       if (opts.interactions && vw === canonical) {
diff --git a/compiler/src/capture/dotlottie.ts b/compiler/src/capture/dotlottie.ts
new file mode 100644
index 0000000..ca7d4da
--- /dev/null
+++ b/compiler/src/capture/dotlottie.ts
@@ -0,0 +1,123 @@
+import { inflateRawSync } from "node:zlib";
+
+/**
+ * dotLottie (.lottie) extraction.
+ *
+ * A `.lottie` file is NOT bare lottie-web JSON — it is a ZIP archive (the "dotLottie"
+ * container) holding `manifest.json` plus one or more `animations/*.json` documents. Feeding
+ * the raw ZIP bytes to lottie-web via `path:` makes it try to JSON.parse a ZIP, which throws
+ * an InvalidStateError at runtime and leaves the container blank. So at materialization time
+ * we detect the ZIP, pick the default/first animation, and rewrite the stored asset as plain
+ * lottie JSON that lottie-web can parse directly.
+ *
+ * Node ships `zlib` (raw DEFLATE) but no ZIP reader, and pulling a zip dependency for this
+ * one shape is overkill — so this implements the minimal slice of the ZIP spec needed:
+ * walking the End-Of-Central-Directory + central directory to locate entries, then reading
+ * each local file header to decompress a stored (method 0) or deflated (method 8) entry.
+ * Deterministic: no timestamps, no randomness, entries resolved by name.
+ */
+
+/** ZIP local file header signature (`PK\x03\x04`). dotLottie archives always start with it. */
+export function isZipArchive(bytes: Buffer): boolean {
+  return bytes.length >= 4 && bytes[0] === 0x50 && bytes[1] === 0x4b && bytes[2] === 0x03 && bytes[3] === 0x04;
+}
+
+const EOCD_SIG = 0x06054b50; // End Of Central Directory
+const CEN_SIG = 0x02014b50; // Central directory file header
+const LOC_SIG = 0x04034b50; // Local file header
+
+type ZipEntry = { name: string; method: number; compSize: number; uncompSize: number; localOffset: number };
+
+/** Locate + read the End-Of-Central-Directory record, then walk the central directory. */
+function readCentralDirectory(buf: Buffer): ZipEntry[] {
+  // The EOCD lives at the tail; it is >=22 bytes and may carry a trailing comment, so scan
+  // backwards for its signature within the max comment window (64KiB) + record size.
+  const minEocd = 22;
+  if (buf.length < minEocd) return [];
+  let eocd = -1;
+  const scanFrom = Math.max(0, buf.length - (0xffff + minEocd));
+  for (let i = buf.length - minEocd; i >= scanFrom; i--) {
+    if (buf.readUInt32LE(i) === EOCD_SIG) { eocd = i; break; }
+  }
+  if (eocd < 0) return [];
+
+  const entryCount = buf.readUInt16LE(eocd + 10);
+  let ptr = buf.readUInt32LE(eocd + 16); // central directory offset
+  const entries: ZipEntry[] = [];
+  for (let i = 0; i < entryCount; i++) {
+    if (ptr + 46 > buf.length || buf.readUInt32LE(ptr) !== CEN_SIG) break;
+    const method = buf.readUInt16LE(ptr + 10);
+    const compSize = buf.readUInt32LE(ptr + 20);
+    const uncompSize = buf.readUInt32LE(ptr + 24);
+    const nameLen = buf.readUInt16LE(ptr + 28);
+    const extraLen = buf.readUInt16LE(ptr + 30);
+    const commentLen = buf.readUInt16LE(ptr + 32);
+    const localOffset = buf.readUInt32LE(ptr + 42);
+    const name = buf.toString("utf8", ptr + 46, ptr + 46 + nameLen);
+    entries.push({ name, method, compSize, uncompSize, localOffset });
+    ptr += 46 + nameLen + extraLen + commentLen;
+  }
+  return entries;
+}
+
+/** Decompress one central-directory entry by reading its local header for the data offset. */
+function readEntry(buf: Buffer, e: ZipEntry): Buffer | null {
+  const p = e.localOffset;
+  if (p + 30 > buf.length || buf.readUInt32LE(p) !== LOC_SIG) return null;
+  // The central directory's name/extra lengths can differ from the local header's, so read the
+  // local header's own lengths to find where the file data begins.
+  const nameLen = buf.readUInt16LE(p + 26);
+  const extraLen = buf.readUInt16LE(p + 28);
+  const dataStart = p + 30 + nameLen + extraLen;
+  const dataEnd = dataStart + e.compSize;
+  if (dataEnd > buf.length) return null;
+  const comp = buf.subarray(dataStart, dataEnd);
+  if (e.method === 0) return Buffer.from(comp); // stored
+  if (e.method === 8) {
+    try { return inflateRawSync(comp); } catch { return null; }
+  }
+  return null; // unsupported compression method
+}
+
+/** Read a named entry (exact path match) from a ZIP buffer, or null if absent/unreadable. */
+export function readZipEntry(buf: Buffer, name: string): Buffer | null {
+  const entry = readCentralDirectory(buf).find((e) => e.name === name);
+  return entry ? readEntry(buf, entry) : null;
+}
+
+/**
+ * Extract the lottie animation JSON from a dotLottie ZIP. Picks the manifest's first/default
+ * animation (falling back to the first `animations/*.json` entry), returning it as a Buffer of
+ * plain lottie JSON ready to hand to lottie-web via `path:`. Returns null when the bytes are
+ * not a dotLottie ZIP or no animation JSON is present.
+ */
+export function extractDotLottieJson(bytes: Buffer): Buffer | null {
+  if (!isZipArchive(bytes)) return null;
+  const entries = readCentralDirectory(bytes);
+  if (!entries.length) return null;
+
+  const animEntries = entries
+    .filter((e) => /^animations\/.+\.json$/i.test(e.name))
+    .sort((a, b) => a.name.localeCompare(b.name)); // deterministic ordering
+  if (!animEntries.length) return null;
+
+  // Prefer the animation the manifest names first (its default), when the manifest is readable.
+  let chosen = animEntries[0]!;
+  const manifestBuf = readZipEntry(bytes, "manifest.json");
+  if (manifestBuf) {
+    try {
+      const manifest = JSON.parse(manifestBuf.toString("utf8")) as { animations?: Array<{ id?: string }> };
+      const firstId = manifest.animations?.[0]?.id;
+      if (firstId) {
+        const match = animEntries.find((e) => e.name === `animations/${firstId}.json`);
+        if (match) chosen = match;
+      }
+    } catch { /* manifest unreadable — keep the name-sorted first animation */ }
+  }
+
+  const json = readEntry(bytes, chosen);
+  if (!json) return null;
+  // Validate it parses as JSON (lottie-web's `path:` loader does a bare JSON.parse).
+  try { JSON.parse(json.toString("utf8")); } catch { return null; }
+  return json;
+}
diff --git a/compiler/src/capture/graft.ts b/compiler/src/capture/graft.ts
index 98323cf..746f0d8 100644
--- a/compiler/src/capture/graft.ts
+++ b/compiler/src/capture/graft.ts
@@ -29,8 +29,14 @@ export const MIN_FRAME_DIM = 48;
 export type FramePlan = "skip" | "still" | "graft";
 
 // Ad/analytics/consent plumbing frames render nothing a visitor values — skip entirely.
+// The trailing group is email-capture / promo POPUP CREATIVE hosts: a vendor whose creative
+// iframe IS a full-viewport interstitial ("Enjoy 15% off" over a dimmed backdrop). Grafting it
+// pours the popup's copy into the DOM/text channel and paints the modal over the real page.
+// CAUTION: these hosts serve OVERLAY creatives, distinct from the vendor's INLINE-form embed
+// hosts (e.g. static-forms.klaviyo.com), which stay graftable — inline signup forms are a
+// deliberately-grafted feature (see iframeGraft tests). Match creative/overlay hosts only.
 const FRAME_SKIP_RE =
-  /(?:doubleclick\.net|googlesyndication\.com|googletagmanager\.com|google-analytics\.com|googleadservices\.com|adservice\.google|facebook\.com\/tr|connect\.facebook\.net|\brecaptcha\b|hcaptcha\.com|challenges\.cloudflare\.com|adsrvr\.org|amazon-adsystem\.com)/i;
+  /(?:doubleclick\.net|googlesyndication\.com|googletagmanager\.com|google-analytics\.com|googleadservices\.com|adservice\.google|facebook\.com\/tr|connect\.facebook\.net|\brecaptcha\b|hcaptcha\.com|challenges\.cloudflare\.com|adsrvr\.org|amazon-adsystem\.com|creatives?\.attn\.tv|\.attentivemobile\.com|bounceexchange\.com|bouncex\.net|\.wunderkind\.co|wknd\.ai|cdn\.justuno\.com\/mkjs|privy\.com\/.*popup|widget\.privy\.com|\.recart\.com|recart\.io)/i;
 // Media players are JS-built canvases/videos whose DOM graft is meaningless; an element
 // screenshot (the poster frame + play chrome) is the faithful static paint.
 const FRAME_STILL_RE =
@@ -165,6 +171,21 @@ export function graftFrameIntoSnapshot(
       x: Math.round((n.bbox.x + frame.contentX) * 100) / 100,
       y: Math.round((n.bbox.y + frame.contentY) * 100) / 100,
     };
+    // Rebase viewport-relative positioning into the frame's box. Inside a real iframe,
+    // `position: fixed` pins to the FRAME's viewport (its content box) and `sticky` scrolls
+    // against the FRAME's scroll container. Grafted in as plain <div> children, those
+    // containing blocks no longer exist, so `fixed` would resolve against the MAIN page
+    // viewport — escaping the iframe's clip box (fixed ignores `overflow:hidden` ancestors)
+    // and painting frame chrome (e.g. a `fixed inset-0 z-[-1]` dark backdrop) across the
+    // whole clone. Demote to box-relative positioning: `fixed`→`absolute` (contained and
+    // clipped by the host div, whose bboxes are already rebased to page coords) and
+    // `sticky`→`relative` (stays in flow instead of sticking to the page scroll). The host
+    // is made a containing block below so these absolutes anchor to the frame box.
+    if (n.computed) {
+      const pos = n.computed.position;
+      if (pos === "fixed") n.computed = { ...n.computed, position: "absolute" };
+      else if (pos === "sticky") n.computed = { ...n.computed, position: "relative" };
+    }
     const a = n.attrs ?? {};
     delete a["data-cid-cap"]; // capture-ids belong to the main document only
     if (a.id) a.id = prefix + a.id;
@@ -184,8 +205,13 @@ export function graftFrameIntoSnapshot(
 
   host.children = [wrapper];
   // A real frame viewport clips its document; the replacement <div> must too, at every
-  // captured viewport (each per-viewport snapshot is grafted independently).
+  // captured viewport (each per-viewport snapshot is grafted independently). It must also
+  // be a containing block: `visit` demoted the frame's `position: fixed` chrome (which was
+  // pinned to the frame viewport) to `absolute`, and those absolutes must anchor to — and
+  // be clipped by — this box, not some positioned ancestor further up the page. A `static`
+  // host wouldn't establish that containing block, so promote it to `relative`.
   host.computed = { ...host.computed, overflow: "hidden", overflowX: "hidden", overflowY: "hidden" };
+  if ((host.computed.position || "static") === "static") host.computed.position = "relative";
   // An iframe is a REPLACED element: `display:inline` (the default) still honors its
   // width/height. The <div> that replaces it at generation is not — inline would collapse
   // the box — so translate to the behavior-equivalent inline-block.
diff --git a/compiler/src/capture/interactions.ts b/compiler/src/capture/interactions.ts
index 3f216c5..48ffeda 100644
--- a/compiler/src/capture/interactions.ts
+++ b/compiler/src/capture/interactions.ts
@@ -24,6 +24,13 @@ const PSEUDO_PROPS = [
 
 export type StyleDelta = Record<string, string>;
 
+/** Changed-properties delta: every key in `b` whose value differs from `a`. Pure (unit-tested). */
+export function diffStyle(a: StyleDelta, b: StyleDelta): StyleDelta {
+  const d: StyleDelta = {};
+  for (const k of Object.keys(b)) if (a[k] !== b[k]) d[k] = b[k]!;
+  return d;
+}
+
 // Properties that distinguish a panel's shown/hidden state and a trigger's
 // active/inactive state. Captured per discrete state so the generated controller
 // can toggle between them faithfully (M2: tabs + accordion).
@@ -363,11 +370,42 @@ export async function captureInteractions(page: Page, opts?: { maxCandidates?: n
       return o;
     }, { capId, props: PSEUDO_PROPS as unknown as string[] });
 
-  const diff = (a: StyleDelta, b: StyleDelta): StyleDelta => {
-    const d: StyleDelta = {};
-    for (const k of Object.keys(b)) if (a[k] !== b[k]) d[k] = b[k]!;
-    return d;
+  const diff = diffStyle;
+
+  // Pseudo-state driver via CDP `CSS.forcePseudoState`. Pointer-based hovering (page.hover)
+  // moves the REAL cursor to the element's box centre, so the browser applies `:hover` to
+  // whatever sits under that point — on a page with a transparent full-viewport overlay (a
+  // fixed page-wrapper / scroll layer, common on modern builder stacks) the point lands on the
+  // overlay and the target never enters `:hover`, silently capturing ZERO authored hover states
+  // even though page.hover throws nothing. Forcing the pseudo-class on the node itself is
+  // geometry-independent (occlusion-immune), applies pure-CSS `:hover` rules directly, and — for
+  // `.card:hover .overlay` — also styles descendants of the forced node, so reveals still show.
+  // Resolves each cap → CDP nodeId; a live map is rebuilt per element (cheap) so it survives
+  // any DOM churn. Falls back to no forcing if a CDP session can't be opened (then hover/focus
+  // capture is simply empty rather than wrong).
+  const client = await page.context().newCDPSession(page).catch(() => null);
+  if (client) {
+    try { await client.send("DOM.enable"); await client.send("CSS.enable"); await client.send("DOM.getDocument", {}); }
+    catch { /* CDP unavailable — force() below no-ops */ }
+  }
+  const nodeIdFor = async (capId: string): Promise<number | null> => {
+    if (!client) return null;
+    let objectId: string | undefined;
+    try {
+      const ev = await client.send("Runtime.evaluate", { expression: `document.querySelector('[data-cid-cap="${capId}"]')` }) as { result?: { objectId?: string } };
+      objectId = ev.result?.objectId; if (!objectId) return null;
+      const r = await client.send("DOM.requestNode", { objectId }) as { nodeId?: number };
+      return r.nodeId ?? null;
+    } catch { return null; }
+    finally { if (objectId) await client.send("Runtime.releaseObject", { objectId }).catch(() => {}); }
   };
+  // Force (or clear, with []) a pseudo-class on a node. Deterministic and reversible.
+  const force = async (nodeId: number | null, classes: string[]): Promise<boolean> => {
+    if (!client || nodeId == null) return false;
+    try { await client.send("CSS.forcePseudoState", { nodeId, forcedPseudoClasses: classes }); return true; }
+    catch { return false; }
+  };
+  const settlePseudo = () => page.waitForTimeout(180); // let a `:hover`/`:focus` transition land
 
   // Reveal-relevant props for descendants that appear on hover (overlay glow + CTA). Only
   // clean show/hide props — NOT transform/filter, whose mid-animation values bake a janky
@@ -413,21 +451,21 @@ export async function captureInteractions(page: Page, opts?: { maxCandidates?: n
   const hoverDesc: Record<string, Record<string, StyleDelta>> = {};
 
   for (const capId of candidates) {
-    const sel = `[data-cid-cap="${capId}"]`;
     const base = await read(capId);
     if (!base) continue;
+    const nodeId = await nodeIdFor(capId);
     const hiddenBase = await readHiddenDesc(capId); // hidden descendants → hover-reveal candidates
     const hiddenCaps = Object.keys(hiddenBase);
-    // :hover — settle before reading: framer-style hover is driven by JS (Framer Motion)
-    // with a short transition, so an immediate read catches the pre-transition frame and
-    // sees no delta (the nav-link hover was missed this way). Wait for the transition to land.
-    try {
-      await page.hover(sel, { timeout: 1200, force: true });
-      await page.waitForTimeout(180);
+    // :hover — force the pseudo-class on the node (geometry-independent; see `force` above),
+    // then settle before reading: an authored `:hover`/JS transition animates from the resting
+    // frame, so an immediate read catches the pre-transition value and sees no delta. Wait for it.
+    if (await force(nodeId, ["hover"])) {
+      await settlePseudo();
       const h = await read(capId);
       if (h) { const d = diff(base, h); if (Object.keys(d).length) hover[capId] = d; }
       // Descendant reveals (while still hovered): a hidden child shown on hover — the card's
-      // OWN style is unchanged, so this is the only signal (framer's "Read story" overlay).
+      // OWN style is unchanged, so this is the only signal (a "Read story" overlay). Forcing
+      // `:hover` on the card also matches `.card:hover .overlay` rules on its descendants.
       if (hiddenCaps.length) {
         await page.waitForTimeout(380); // let the reveal transition fully finish before reading
         const after = await readDescProps(hiddenCaps);
@@ -444,16 +482,17 @@ export async function captureInteractions(page: Page, opts?: { maxCandidates?: n
         }
         if (Object.keys(revealed).length) hoverDesc[capId] = revealed;
       }
-    } catch { /* not hoverable (covered/offscreen) — skip */ }
-    await page.mouse.move(1, 1).catch(() => {});
-    // :focus (only for focusable-ish; cheap to attempt, guarded)
-    try {
-      await page.focus(sel, { timeout: 800 });
+      await force(nodeId, []); // clear :hover before probing :focus
+    }
+    // :focus — force the pseudo-class the same way (also occlusion-independent).
+    if (await force(nodeId, ["focus"])) {
+      await settlePseudo();
       const f = await read(capId);
       if (f) { const d = diff(base, f); if (Object.keys(d).length) focus[capId] = d; }
-      await page.evaluate(() => (document.activeElement as HTMLElement | null)?.blur());
-    } catch { /* not focusable — skip */ }
+      await force(nodeId, []); // restore the resting state
+    }
   }
+  await client?.detach().catch(() => {});
 
   log({ event: "interactions_hover_focus", candidates: candidates.length, hover: Object.keys(hover).length, focus: Object.keys(focus).length, hoverDesc: Object.keys(hoverDesc).length });
 
diff --git a/compiler/src/capture/motion.ts b/compiler/src/capture/motion.ts
index 1dcc955..5edfe7f 100644
--- a/compiler/src/capture/motion.ts
+++ b/compiler/src/capture/motion.ts
@@ -60,6 +60,83 @@ export type MarqueeSpec = {
   periodPx: number; // distance per seamless loop (one duplicated copy ≈ scrollWidth/2)
 };
 
+// ---- Pure marquee discriminators (extracted so the in-browser sampling logic is unit
+// testable). These are duplicated verbatim inside `detectMarquees`' page.evaluate body —
+// module-scope functions do NOT cross the serialization boundary — so any change here must
+// be mirrored there (and vice versa). They are deterministic: no randomness, no clock reads.
+
+/**
+ * Median signed velocity (px/s) from a series of per-sample translateX deltas taken at a
+ * fixed cadence. Median (not mean) ignores the single per-loop wrap-reset outlier, which
+ * is a large jump opposite the travel direction when the track seamlessly restarts.
+ */
+export function medianVelocityPxPerSec(deltas: number[], sampleMs: number): number {
+  if (!deltas.length || sampleMs <= 0) return 0;
+  const med = [...deltas].sort((a, b) => a - b)[Math.floor(deltas.length / 2)]!;
+  return Math.round((med / sampleMs) * 1000);
+}
+
+/**
+ * Discriminator 2 — sustained-constant-velocity test. A real marquee holds a steady
+ * velocity across time; a scroll-settle lerp (still easing toward its scroll-target after
+ * `scrollIntoView`) decays, so its velocity in a later observation window is a small
+ * fraction of the earlier one. Two windows of per-sample deltas separated by ≥1.5s; pass
+ * only if the later window's speed is BOTH non-trivial AND close to the earlier window's
+ * (within a relative tolerance) — i.e. it did not decay and did not reverse.
+ *
+ * @param window1Deltas per-sample translateX deltas from the first observation window
+ * @param window2Deltas per-sample translateX deltas from the second (later) window
+ * @param sampleMs cadence between samples within a window
+ * @param minPxPerSec minimum sustained |velocity| to be considered moving at all
+ * @param relTol fractional tolerance: |v2| must be ≥ (1-relTol)·|v1| and same sign
+ */
+export function classifyVelocitySamples(
+  window1Deltas: number[],
+  window2Deltas: number[],
+  sampleMs: number,
+  minPxPerSec = 4,
+  relTol = 0.5,
+): { isMarquee: boolean; pxPerSec: number; v1: number; v2: number } {
+  const v1 = medianVelocityPxPerSec(window1Deltas, sampleMs);
+  const v2 = medianVelocityPxPerSec(window2Deltas, sampleMs);
+  // The reported velocity is the first window's (measured closest to a clean, post-settle
+  // marquee; also what the old code reported), kept for output determinism vs. the old path.
+  const pxPerSec = v1;
+  if (Math.abs(v1) < minPxPerSec || Math.abs(v2) < minPxPerSec) return { isMarquee: false, pxPerSec, v1, v2 };
+  if (Math.sign(v1) !== Math.sign(v2)) return { isMarquee: false, pxPerSec, v1, v2 }; // reversed → not a steady ticker
+  // v2 must NOT have decayed relative to v1 (a lerp settling toward target loses speed).
+  const sustained = Math.abs(v2) >= Math.abs(v1) * (1 - relTol);
+  return { isMarquee: sustained, pxPerSec, v1, v2 };
+}
+
+/**
+ * Discriminator 4 — genuine duplicated content. A marquee duplicates its content ≥2×
+ * (that is how a seamless loop works); "≥2 children" alone is far too weak (any flex row
+ * of distinct logos passes). Require actual repetition: ≥2 CONSECUTIVE children whose
+ * shape repeats — equal outerHTML hash (exact duplicate) or, as a looser structural
+ * fallback, an equal consecutive width sequence (some marquees clone then tweak attributes
+ * so hashes differ but the geometry repeats).
+ *
+ * @param hashes per-child outerHTML hash (cheap 32-bit), index-aligned with `widths`
+ * @param widths per-child rounded offsetWidth
+ */
+export function hasRepeatedChildren(hashes: number[], widths: number[]): boolean {
+  const n = Math.min(hashes.length, widths.length);
+  if (n < 2) return false;
+  // (a) two consecutive children with an identical hash — a literal cloned copy.
+  for (let i = 1; i < n; i++) if (hashes[i] === hashes[i - 1] && hashes[i] !== 0) return true;
+  // (b) structural fallback: the first half's width sequence repeats in the second half
+  // (content duplicated as a block, e.g. [A B C A B C]). Require an even count and a real
+  // width so a row of zero-width nodes can't spuriously "repeat".
+  if (n >= 4 && n % 2 === 0) {
+    const half = n / 2;
+    let repeats = true;
+    for (let i = 0; i < half; i++) { if (widths[i] === 0 || widths[i] !== widths[i + half]) { repeats = false; break; } }
+    if (repeats) return true;
+  }
+  return false;
+}
+
 export type MotionCapture = {
   waapi: WaapiAnim[];
   rotators: RotatorSpec[];
@@ -132,6 +209,25 @@ export async function probeReveals(page: Page): Promise<void> {
  * and record its signed velocity + seamless-loop period (one duplicated copy ≈ half the
  * scroll width) so the clone can replay the loop. Read-only beyond scrolling (restores
  * scroll to top); does not touch the captured snapshot/IR.
+ *
+ * Discriminators (ALL must pass — a candidate is only classified as a marquee if every one
+ * holds), added to defeat scroll-LINKED easing false positives (a static logo row on a
+ * scroll-eased page is still lerping toward its scroll-target right after `scrollIntoView`,
+ * which reads as a constant velocity over a single short window):
+ *   1. Content overflow — scrollWidth > 1.35·clientWidth (a marquee has content to scroll;
+ *      a static row that fits its box, scrollWidth ≈ clientWidth, cannot be a marquee).
+ *   2. Sustained constant velocity — two observation windows separated by ≥1.5s; a settle
+ *      lerp decays (v2 ≪ v1), a real marquee holds v2 ≈ v1 (see classifyVelocitySamples).
+ *   3. Scroll independence (jiggle) — nudge scroll by ±50px and re-sample; if the velocity
+ *      responds to the nudge the motion is scroll-linked, not a self-driven ticker.
+ *   4. Genuine duplication — ≥2 consecutive children repeat (equal outerHTML hash or an
+ *      equal consecutive width sequence), the shape real marquees use for a seamless loop.
+ *
+ * Added latency is bounded: the expensive per-candidate windows/jiggle run ONLY for the
+ * few candidates that already pass the cheap synchronous gates (overflow + translated +
+ * clip + duplication), and the candidate list is capped at 8. Per surviving candidate the
+ * async cost is ≈ 300ms settle + 2×~600ms windows + ~1.4s inter-window gap + 2×~250ms
+ * jiggle ≈ 3.4s; with the cap the whole pass is bounded regardless of page size.
  */
 async function detectMarquees(page: Page): Promise<MarqueeSpec[]> {
   try {
@@ -143,32 +239,113 @@ async function detectMarquees(page: Page): Promise<MarqueeSpec[]> {
         while (p && depth < 6) { const ox = getComputedStyle(p).overflowX; if (ox === "hidden" || ox === "clip") return true; p = p.parentElement; depth++; }
         return false;
       };
+      // cheap 32-bit string hash (djb2-ish) — deterministic, for the duplication test.
+      const hashStr = (s: string): number => { let h = 5381; for (let i = 0; i < s.length; i++) h = ((h << 5) + h + s.charCodeAt(i)) | 0; return h; };
+
+      // ---- Pure discriminators (mirror of the exported module-scope functions; kept inline
+      // because module scope does not cross the page.evaluate serialization boundary). ----
+      const medianVelocityPxPerSec = (deltas: number[], sampleMs: number): number => {
+        if (!deltas.length || sampleMs <= 0) return 0;
+        const med = [...deltas].sort((a, b) => a - b)[Math.floor(deltas.length / 2)]!;
+        return Math.round((med / sampleMs) * 1000);
+      };
+      const classifyVelocitySamples = (w1: number[], w2: number[], sampleMs: number, minPxPerSec = 4, relTol = 0.5) => {
+        const v1 = medianVelocityPxPerSec(w1, sampleMs);
+        const v2 = medianVelocityPxPerSec(w2, sampleMs);
+        const pxPerSec = v1;
+        if (Math.abs(v1) < minPxPerSec || Math.abs(v2) < minPxPerSec) return { isMarquee: false, pxPerSec, v1, v2 };
+        if (Math.sign(v1) !== Math.sign(v2)) return { isMarquee: false, pxPerSec, v1, v2 };
+        const sustained = Math.abs(v2) >= Math.abs(v1) * (1 - relTol);
+        return { isMarquee: sustained, pxPerSec, v1, v2 };
+      };
+      const hasRepeatedChildren = (hashes: number[], widths: number[]): boolean => {
+        const n = Math.min(hashes.length, widths.length);
+        if (n < 2) return false;
+        for (let i = 1; i < n; i++) if (hashes[i] === hashes[i - 1] && hashes[i] !== 0) return true;
+        if (n >= 4 && n % 2 === 0) {
+          const half = n / 2;
+          let repeats = true;
+          for (let i = 0; i < half; i++) { if (widths[i] === 0 || widths[i] !== widths[i + half]) { repeats = false; break; } }
+          if (repeats) return true;
+        }
+        return false;
+      };
+      // sample per-child outerHTML hash + width for the duplication test.
+      const childSignature = (el: Element): { hashes: number[]; widths: number[] } => {
+        const hashes: number[] = [], widths: number[] = [];
+        const kids = Array.from(el.children).slice(0, 24) as HTMLElement[];
+        for (const k of kids) { hashes.push(hashStr(k.outerHTML)); widths.push(Math.round(k.getBoundingClientRect().width)); }
+        return { hashes, widths };
+      };
+      // one observation window: `count` deltas at `sampleMs` cadence.
+      const sampleWindow = async (el: Element, count: number, sampleMs: number): Promise<number[]> => {
+        const xs: number[] = [txOf(el)];
+        for (let i = 0; i < count; i++) { await sleep(sampleMs); xs.push(txOf(el)); }
+        const dxs: number[] = []; for (let i = 1; i < xs.length; i++) dxs.push(xs[i]! - xs[i - 1]!);
+        return dxs;
+      };
+
+      const SAMPLE_MS = 120;
+      const WINDOW_SAMPLES = 5;            // 5 deltas ≈ 600ms per window
+      const INTER_WINDOW_MS = 1500;        // ≥1.5s between windows (discriminator 2)
+      const JIGGLE_PX = 50;                // scroll nudge for the independence test (discriminator 3)
+
       // Candidates: tagged, already translated (paused tickers keep their offset), with
-      // duplicated content (≥2 children) inside an overflow-clip viewport — the marquee shape.
+      // GENUINE duplicated content inside an overflow-clip viewport, AND real content
+      // overflow (scrollWidth > 1.35·clientWidth) — the marquee shape. All cheap/synchronous
+      // so the expensive async windows only run for the few survivors.
       const cand: Element[] = [];
       for (const el of Array.from(document.querySelectorAll("[data-cid-cap]"))) {
         if (Math.abs(txOf(el)) <= 0.5) continue;
         if (el.children.length < 2) continue;
         if (!inClip(el)) continue;
+        // Discriminator 1: content overflow. scrollWidth must meaningfully exceed clientWidth;
+        // a static row that fits (scrollWidth ≈ clientWidth) has nothing to scroll.
+        if (el.scrollWidth <= el.clientWidth * 1.35) continue;
+        // Discriminator 4: genuine repetition, not merely ≥2 distinct children.
+        const sig = childSignature(el);
+        if (!hasRepeatedChildren(sig.hashes, sig.widths)) continue;
         cand.push(el);
-        if (cand.length >= 16) break;
+        if (cand.length >= 8) break;
       }
       const out: Array<{ cap: string; axis: "x"; pxPerSec: number; periodPx: number }> = [];
       const seen = new Set<string>();
       for (const el of cand) {
         const cap = el.getAttribute("data-cid-cap"); if (!cap || seen.has(cap)) continue;
         try { el.scrollIntoView({ block: "center" }); } catch { /* ignore */ }
-        await sleep(450); // wake the off-screen-paused ticker + let the scroll settle
-        const xs: number[] = [];
-        for (let i = 0; i < 6; i++) { xs.push(txOf(el)); await sleep(120); }
-        const dxs: number[] = []; for (let i = 1; i < xs.length; i++) dxs.push(xs[i]! - xs[i - 1]!);
-        if (dxs.length < 3) continue;
-        // velocity = median per-120ms delta (median ignores the single wrap-reset outlier).
-        const med = [...dxs].sort((a, b) => a - b)[Math.floor(dxs.length / 2)]!;
-        const pxPerSec = Math.round((med / 120) * 1000);
-        if (Math.abs(pxPerSec) < 4) continue; // not actually moving (e.g. a frozen scroll-scrub offset)
-        // direction must be consistent in all but (at most) the one wrap step.
-        if (dxs.filter((d) => Math.sign(d) === Math.sign(med)).length < dxs.length - 1) continue;
+        await sleep(300); // wake the off-screen-paused ticker + let the scroll settle
+
+        // Discriminator 2: two velocity windows ≥1.5s apart. A scroll-settle lerp decays;
+        // a real marquee holds constant velocity.
+        const w1 = await sampleWindow(el, WINDOW_SAMPLES, SAMPLE_MS);
+        await sleep(INTER_WINDOW_MS);
+        const w2 = await sampleWindow(el, WINDOW_SAMPLES, SAMPLE_MS);
+        if (w1.length < 3 || w2.length < 3) continue;
+        // direction must be consistent within window 1, but for (at most) the one wrap step.
+        const med1 = [...w1].sort((a, b) => a - b)[Math.floor(w1.length / 2)]!;
+        if (w1.filter((d) => Math.sign(d) === Math.sign(med1)).length < w1.length - 1) continue;
+        const cls = classifyVelocitySamples(w1, w2, SAMPLE_MS);
+        if (!cls.isMarquee) continue;
+        const pxPerSec = cls.pxPerSec;
+
+        // Discriminator 3: scroll independence (jiggle). Nudge the scroll ±50px and re-sample
+        // velocity; a self-driven ticker is unaffected, a scroll-linked animation changes.
+        const baseY = window.scrollY;
+        const jiggle = async (dy: number): Promise<number> => {
+          try { window.scrollTo(0, Math.max(0, baseY + dy)); } catch { /* ignore */ }
+          await sleep(250); // let any scroll-linked easing react and settle at the new offset
+          const dxs = await sampleWindow(el, WINDOW_SAMPLES, SAMPLE_MS);
+          return medianVelocityPxPerSec(dxs, SAMPLE_MS);
+        };
+        const vDown = await jiggle(JIGGLE_PX);
+        const vUp = await jiggle(-JIGGLE_PX);
+        try { window.scrollTo(0, baseY); } catch { /* ignore */ }
+        // Scroll-linked motion responds to the nudge (velocity reverses, dies, or spikes as
+        // it re-lerps to the new target). A real marquee holds ~pxPerSec through both nudges.
+        const stableUnderJiggle = (v: number): boolean =>
+          Math.sign(v) === Math.sign(pxPerSec) && Math.abs(v) >= Math.abs(pxPerSec) * 0.5 && Math.abs(v) <= Math.abs(pxPerSec) * 2;
+        if (!stableUnderJiggle(vDown) || !stableUnderJiggle(vUp)) continue;
+
         const periodPx = Math.round(el.scrollWidth / 2);
         if (periodPx < 40) continue;
         seen.add(cap);
@@ -305,8 +482,11 @@ export async function captureMotion(page: Page, opts?: { observeMs?: number; log
             const cap = el && (el as Element).getAttribute?.("data-cid-cap");
             if (!cap) continue;
             const elem = el as Element;
-            // only track small text-bearing elements (a rotating word/phrase, not a big block)
-            if (elem.querySelector("[data-cid-cap]")) continue; // has element children → not a leaf word
+            // only track small text-bearing elements (a rotating word/phrase, not a big block).
+            // Reject ANY element child, capped or not: rows injected at runtime (after cid-cap
+            // tagging, so uncapped) would otherwise defeat a capped-only check and let a
+            // multi-element panel pass as a "leaf word".
+            if (elem.firstElementChild) continue; // has element children → not a leaf word
             const txt = norm(elem.textContent || "");
             if (!txt || txt.length > 80) continue;
             const e = changes.get(cap) ?? { texts: [], times: [] };
diff --git a/compiler/src/capture/walker.ts b/compiler/src/capture/walker.ts
index 360982e..0cb039b 100644
--- a/compiler/src/capture/walker.ts
+++ b/compiler/src/capture/walker.ts
@@ -44,6 +44,18 @@ export type RawNode = {
   computed: RawStyle;
   bbox: RawBBox;
   visible: boolean;
+  // A font-metric / measurement scratch node injected by the SOURCE site's own JS (typography
+  // libraries, FontFaceObserver): absolutely positioned, parked far off-screen, and non-painting.
+  // Never user-visible; excluded from emission so it doesn't ship as page markup.
+  probe?: boolean;
+  // This element hosts an OPEN shadow root: its serialized children are the composed (flattened)
+  // shadow tree — the shadowRoot's children with each <slot> replaced by its assigned light-DOM
+  // nodes — NOT the host's light-DOM children. Custom elements (`<product-info>`) render all their
+  // swatches/title/price inside this shadow tree, so a childNodes-only walk captured them empty.
+  shadowHost?: boolean;
+  // This node was serialized from inside a shadow tree (a shadowRoot descendant, or the shadow
+  // subtree of a slotted light node). Tagged so generation can emit it as ordinary light DOM.
+  inShadow?: boolean;
   sizing?: RawSizing;
   before?: RawStyle;
   after?: RawStyle;
@@ -51,6 +63,10 @@ export type RawNode = {
   // clone renders the browser's default gray, losing the authored placeholder color/type.
   placeholder?: RawStyle;
   rawHTML?: string; // set for inline <svg>
+  // Computed paint of an inline <svg> root (fill/stroke/color). A raw `fill="none"` attribute may
+  // still resolve to a real paint via site CSS (`fill: currentColor`); these resolved values let
+  // codegen recover a paint the extraction stripped. Set only for svg roots.
+  svgPaint?: { fill: string; stroke: string; color: string };
   children: RawChild[];
 };
 
@@ -64,6 +80,10 @@ export type FontFace = {
   display?: string;
   unicodeRange?: string;
   stretch?: string;
+  // Url of the stylesheet this face was declared in (undefined for an inline <style>, or for faces
+  // parsed out-of-band where the base is already baked into `src`). The src descriptor's relative
+  // url()s resolve against this, not the document — see readRules and parseSrcUrls.
+  baseHref?: string;
 };
 
 export type PageSnapshot = {
@@ -134,6 +154,11 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
     "letterSpacing", "wordSpacing", "textAlign", "textTransform",
     "textDecorationLine", "textDecorationColor", "textDecorationStyle",
     "whiteSpace", "wordBreak", "overflowWrap", "textOverflow", "textIndent",
+    // Modern line-wrapping: `text-wrap: balance/pretty` rebalances heading line breaks
+    // (getComputedStyle reports the shorthand — "balance"/"pretty"/"wrap"). Without it a
+    // balanced heading wraps differently in the clone (an even two-line title collapses
+    // to a lopsided break). Default "wrap" is elided downstream.
+    "textWrap",
     "textShadow", "fontVariantCaps", "fontFeatureSettings",
     // Line clamping (`display:-webkit-box; -webkit-box-orient:vertical; -webkit-line-clamp:N`):
     // the mechanism that keeps cards equal height regardless of text length. Without it the engine
@@ -286,7 +311,24 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
     return true;
   };
 
-  const serializeElement = (el: Element): RawNode | null => {
+  // A measurement/probe scratch node: out-of-flow (absolute/fixed), parked far off-screen
+  // (≥10000px beyond any edge — real drawers/sr-only content never live out there), AND
+  // non-painting (visibility:hidden / collapse / opacity:0). The two together are exclusive to
+  // font-metric / measurement scratch elements the source's own JS injects (a11y sr-only text
+  // stays visibility:visible so AT can read it, so it never matches). Tagged so emission drops it.
+  const OFFSCREEN_PROBE_PX = 10000;
+  const isProbe = (cs: CSSStyleDeclaration, bbox: RawBBox): boolean => {
+    if (cs.position !== "absolute" && cs.position !== "fixed") return false;
+    const nonPainting = cs.visibility === "hidden" || cs.visibility === "collapse" || parseFloat(cs.opacity || "1") === 0;
+    if (!nonPainting) return false;
+    const rightEdge = bbox.x + bbox.width;
+    const bottomEdge = bbox.y + bbox.height;
+    const pageH = round2(scrollEl.scrollHeight);
+    return rightEdge <= -OFFSCREEN_PROBE_PX || bottomEdge <= -OFFSCREEN_PROBE_PX
+      || bbox.x >= OFFSCREEN_PROBE_PX + vpW || bbox.y >= OFFSCREEN_PROBE_PX + pageH;
+  };
+
+  const serializeElement = (el: Element, inShadow = false): RawNode | null => {
     if (nodeCount >= MAX_NODES) { truncated = true; return null; }
     const tag = el.tagName.toLowerCase();
     nodeCount++;
@@ -359,9 +401,36 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
         const hf = el.getBoundingClientRect().height;
         // Tight 0.5px: only call a dimension "reproduced" when auto/100% lands essentially exactly,
         // so a drop can't accumulate a visible shift across many elements (favours fidelity).
+        let hAuto = Math.abs(ha - r.height) <= 0.5;
+        let hFill = Math.abs(hf - r.height) <= 0.5;
+        // Circular-height guard: a box whose fill child (height:100%) pins it back up makes BOTH
+        // `height:auto` and `height:100%` reproduce the box, so the raw verdict reads hAuto (drop) —
+        // even though the height is authored (e.g. `100vh` on a hero, an explicit px section). Both
+        // sides then wait on each other and the box collapses. When this element's own cascade/inline
+        // style declares an explicit definite height, trust that declaration: the height is authored,
+        // so it is neither content-sized (hAuto) nor a parent fill (hFill). Only overrides when auto
+        // actually reproduced — a genuine explicit height that auto already shrinks stays hAuto:false.
+        if ((hAuto || hFill) && r.height > 2 && authorsExplicitHeight(el, sh)) {
+          hAuto = false;
+          hFill = false;
+        }
+        let wAuto = Math.abs(wa - r.width) <= 0.5;
+        let wFill = Math.abs(wf - r.width) <= 0.5;
+        // Circular-WIDTH guard (the mirror of the height guard above): an authored `width:24px` inside a
+        // SHRINK-TO-FIT parent (a color-swatch link in a span that shrink-wraps to it) makes BOTH
+        // `width:auto` and `width:100%` reproduce the box — the parent's width still holds while the
+        // child re-measures — so the raw verdict reads wAuto/wFill (drop) and the clone collapses the
+        // child to 0 content width (and the shrink-wrap span to its borders). When this element's own
+        // cascade/inline style declares an explicit definite width, trust it: the width is authored, so
+        // it is neither content-sized (wAuto) nor a parent fill (wFill). Only overrides when a probe
+        // actually reproduced — a genuine explicit width that auto already shrinks stays wAuto:false.
+        if ((wAuto || wFill) && r.width > 2 && authorsExplicitWidth(el, sw)) {
+          wAuto = false;
+          wFill = false;
+        }
         sizing = {
-          wAuto: Math.abs(wa - r.width) <= 0.5, wFill: Math.abs(wf - r.width) <= 0.5, hAuto: Math.abs(ha - r.height) <= 0.5,
-          hFill: Math.abs(hf - r.height) <= 0.5,
+          wAuto, wFill, hAuto,
+          hFill,
           wMin: Math.round(wmin * 100) / 100, wMax: Math.round(wmax * 100) / 100,
         };
       } finally {
@@ -401,6 +470,8 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
       computed,
       bbox,
       visible: isVisible(el, cs, bbox),
+      ...(isProbe(cs, bbox) ? { probe: true } : {}),
+      ...(inShadow ? { inShadow: true } : {}),
       ...(sizing ? { sizing } : {}),
       children: [],
     };
@@ -429,6 +500,14 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
     // Inline SVG → raw markup, no recursion.
     if (tag === "svg") {
       node.rawHTML = el.outerHTML;
+      // Capture the svg root's COMPUTED paint (fill/stroke/color) separately from the general
+      // computed-prop list. A raw `fill="none"` presentation attribute paints nothing on its own; a
+      // wordmark/icon is visible on the source only because site CSS (a `fill: currentColor` class,
+      // an inherited `color`) overrides it. Extraction strips that CSS, so the raw attribute alone is
+      // misleading — codegen consults these resolved values to decide whether the root truly paints.
+      try {
+        node.svgPaint = { fill: cs.fill, stroke: cs.stroke, color: cs.color };
+      } catch { /* getComputedStyle already read above; guard against exotic UAs */ }
       return node;
     }
 
@@ -436,8 +515,28 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
     // code blocks with highlighted spans separated by newlines).
     const preserveWs = /^(pre|pre-wrap|break-spaces)/.test(cs.whiteSpace || "");
 
+    // Composed (flattened) child list — the tree the user actually sees, matching what
+    // getComputedStyle/getBoundingClientRect already report for every node:
+    //   - An open shadow HOST renders its shadow tree, not its light children: iterate the
+    //     shadowRoot's children and tag them (and the host) so generation emits them as light DOM.
+    //   - A <slot> is a placeholder for the light-DOM nodes distributed into it: replace it with its
+    //     assignedNodes (or its own fallback children when nothing is assigned). Assigned nodes are
+    //     the author's real light content, so they are NOT tagged inShadow — only genuine shadow
+    //     descendants are. Walking the shadow tree (never the host's raw light children) means a
+    //     slotted child is serialized once, at the slot position, with no double-emission.
+    const sr = (el as HTMLElement).shadowRoot; // open roots only; closed roots are null here
+    let childInShadow = inShadow;
+    let childNodes: Node[];
+    if (sr) {
+      node.shadowHost = true;
+      childInShadow = true;
+      childNodes = Array.from(sr.childNodes);
+    } else {
+      childNodes = Array.from(el.childNodes);
+    }
+
     // Recurse children (elements + text nodes), preserving order.
-    for (const child of Array.from(el.childNodes)) {
+    for (const child of childNodes) {
       if (child.nodeType === Node.TEXT_NODE) {
         const t = child.textContent || "";
         if (preserveWs && t.length > 0) {
@@ -457,8 +556,28 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
       }
       if (child.nodeType !== Node.ELEMENT_NODE) continue;
       const childEl = child as Element;
-      if (SKIP_TAGS.has(childEl.tagName.toLowerCase())) continue;
-      const sn = serializeElement(childEl);
+      const childTag = childEl.tagName.toLowerCase();
+      if (SKIP_TAGS.has(childTag)) continue;
+      // A slot nested deeper inside a shadow tree: expand its assigned light nodes in place. The
+      // assigned nodes are light DOM (author content), so they drop back to inShadow=false.
+      if (childTag === "slot" && childInShadow) {
+        const assigned = (childEl as HTMLSlotElement).assignedNodes({ flatten: true });
+        const slotKids = assigned.length ? assigned : Array.from(childEl.childNodes);
+        for (const sk of slotKids) {
+          if (sk.nodeType === Node.TEXT_NODE) {
+            const t = sk.textContent || "";
+            if (t.trim().length > 0) node.children.push({ text: t });
+            continue;
+          }
+          if (sk.nodeType !== Node.ELEMENT_NODE) continue;
+          const skEl = sk as Element;
+          if (SKIP_TAGS.has(skEl.tagName.toLowerCase())) continue;
+          const skn = serializeElement(skEl, assigned.length ? false : true);
+          if (skn) node.children.push(skn);
+        }
+        continue;
+      }
+      const sn = serializeElement(childEl, childInShadow);
       if (sn) node.children.push(sn);
     }
 
@@ -470,22 +589,107 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
   const cssUrlSet = new Set<string>();
   const keyframes: string[] = [];
   const cssVars: Record<string, string> = {};
+  // Selectors that AUTHOR an explicit, definite height/min-height (px/rem/em/vh/vw/…,
+  // NOT auto, NOT a percentage, NOT a keyword). Harvested once from the cascade below and
+  // consulted by the sizing probe to break circular parent/child height verdicts: when a box
+  // and its fill child mutually justify each other's height, `height:auto` reproduces the box
+  // for a reason that is NOT "content-sized", so the probe alone reads hAuto:true and the
+  // authored dimension gets dropped downstream. A declared explicit length is ground truth that
+  // the height is load-bearing, so we trust the declaration over the reflow verdict.
+  const explicitHeightSelectors: string[] = [];
+  // The WIDTH twin of explicitHeightSelectors: selectors that author an explicit definite `width`/
+  // `min-width` (px/rem/em/…, not auto/%/keyword). Consulted by the sizing probe to break a CIRCULAR
+  // width verdict — an authored `width:24px` inside a shrink-to-fit parent reproduces at both auto and
+  // 100% (the parent's width still holds), so the probe alone reads wAuto and the authored width gets
+  // dropped, collapsing the box in the clone.
+  const explicitWidthSelectors: string[] = [];
 
-  const absUrl = (u: string): string => {
-    try { return new URL(u, document.baseURI).href; } catch { return u; }
+  const absUrl = (u: string, base?: string): string => {
+    try { return new URL(u, base || document.baseURI).href; } catch { return u; }
   };
 
-  const harvestUrlsFromText = (text: string): void => {
+  // A relative url() inside a stylesheet resolves against THAT STYLESHEET'S url, not the document —
+  // `url("../media/x.woff2")` in `/a/b/css/sheet.css` points at `/a/b/media/x.woff2`, which is a
+  // different file from the document-relative `/media/x.woff2`. Resolving font/image srcs against
+  // `document.baseURI` fetches the wrong path (often the SPA router's 200+HTML shell), so a harvested
+  // face src must carry its owning sheet's base. Walk up through `@import` nesting (parentStyleSheet
+  // via ownerRule) to the nearest sheet that actually has an href; an inline `<style>` has none, so
+  // it correctly falls back to the document base.
+  const sheetBaseHref = (sheet: CSSStyleSheet | null | undefined): string | undefined => {
+    let s: CSSStyleSheet | null | undefined = sheet;
+    // Bound the walk defensively; @import chains are shallow in practice.
+    for (let i = 0; s && i < 32; i++) {
+      if (s.href) return s.href;
+      s = s.ownerRule?.parentStyleSheet ?? null;
+    }
+    return undefined;
+  };
+
+  const harvestUrlsFromText = (text: string, base?: string): void => {
     const re = /url\(\s*(['"]?)([^'")]+)\1\s*\)/g;
     let m: RegExpExecArray | null;
     while ((m = re.exec(text)) !== null) {
       const raw = m[2];
       if (!raw || raw.startsWith("data:")) continue;
-      cssUrlSet.add(absUrl(raw));
+      cssUrlSet.add(absUrl(raw, base));
     }
   };
 
-  const readRules = (rules: CSSRuleList): void => {
+  // True when a `height`/`min-height` value is an explicit, definite length the browser resolves
+  // to a fixed px box (px/rem/em/vh/vw/vmin/vmax/ch/…, or a calc/min/max/clamp over them). False for
+  // `auto`, an empty value, a pure percentage (resolves against the parent — that's the fill case the
+  // hFill probe already handles), `0`, and intrinsic keywords (fit-/min-/max-content). A definite
+  // authored height is load-bearing and must survive even when the reflow probe reads hAuto:true.
+  const isExplicitHeight = (raw: string): boolean => {
+    const v = (raw || "").trim().toLowerCase();
+    if (!v || v === "auto" || v === "0" || v === "0px" || v === "none") return false;
+    if (v === "fit-content" || v === "min-content" || v === "max-content" || v === "inherit" ||
+      v === "initial" || v === "unset" || v === "revert" || v === "revert-layer") return false;
+    // A bare percentage resolves against the parent (fill), not an authored definite length.
+    if (/^[\d.]+%$/.test(v)) return false;
+    // A definite length unit (or a calc()/min()/max()/clamp() that contains one) anchors the box.
+    return /(?:^|[\s(*/+-])[\d.]+(?:px|rem|em|vh|vw|vmin|vmax|svh|lvh|dvh|cm|mm|in|pt|pc|ex|ch|q)\b/.test(v);
+  };
+
+  // Does this element author an explicit definite height — via its own inline style (passed as
+  // `inlineHeight`, already read by the probe) or via any matched cascade rule harvested into
+  // `explicitHeightSelectors`? getComputedStyle resolves height to used px (so `100vh` reads as a
+  // plain number and is indistinguishable from a content height there); the specified value is only
+  // recoverable from the inline declaration and the cascade, which is why we consult both.
+  const authorsExplicitHeight = (el: Element, inlineHeight: string): boolean => {
+    if (isExplicitHeight(inlineHeight)) return true;
+    try {
+      const inlineMin = (el as HTMLElement).style?.getPropertyValue("min-height") || "";
+      if (isExplicitHeight(inlineMin)) return true;
+    } catch { /* ignore */ }
+    for (const sel of explicitHeightSelectors) {
+      try { if (el.matches(sel)) return true; } catch { /* invalid/unsupported selector */ }
+    }
+    return false;
+  };
+
+  // The WIDTH twin of authorsExplicitHeight: does this element author an explicit definite width via
+  // its own inline style (`inlineWidth`, already read by the probe) or any matched harvested rule?
+  // `isExplicitHeight` is unit-agnostic (it only rejects auto/%/keywords and matches definite lengths),
+  // so it doubles as the width predicate.
+  const authorsExplicitWidth = (el: Element, inlineWidth: string): boolean => {
+    if (isExplicitHeight(inlineWidth)) return true;
+    try {
+      const inlineMin = (el as HTMLElement).style?.getPropertyValue("min-width") || "";
+      if (isExplicitHeight(inlineMin)) return true;
+    } catch { /* ignore */ }
+    for (const sel of explicitWidthSelectors) {
+      try { if (el.matches(sel)) return true; } catch { /* invalid/unsupported selector */ }
+    }
+    return false;
+  };
+
+  // `base` is the url of the stylesheet these rules live in (undefined for an inline <style>, which
+  // resolves against the document). It is threaded so every harvested url() — @font-face src and
+  // ordinary style-rule url() alike — resolves relative to its OWNING sheet, not the page. The src
+  // string is left verbatim on the FontFace (parseSrcUrls re-absolutizes it downstream against the
+  // same base), but the base still drives the cssUrlSet entry that triggers the download.
+  const readRules = (rules: CSSRuleList, base?: string): void => {
     for (const rule of Array.from(rules)) {
       const type = rule.constructor.name;
       if (type === "CSSFontFaceRule") {
@@ -502,26 +706,40 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
             display: s.getPropertyValue("font-display") || undefined,
             unicodeRange: s.getPropertyValue("unicode-range") || undefined,
             stretch: s.getPropertyValue("font-stretch") || undefined,
+            baseHref: base,
           });
-          harvestUrlsFromText(src);
+          harvestUrlsFromText(src, base);
         }
       } else if (type === "CSSKeyframesRule") {
         keyframes.push((rule as CSSKeyframesRule).cssText);
       } else if (type === "CSSStyleRule") {
         const r = rule as CSSStyleRule;
-        if (r.style && r.style.cssText.includes("url(")) harvestUrlsFromText(r.style.cssText);
+        if (r.style && r.style.cssText.includes("url(")) harvestUrlsFromText(r.style.cssText, base);
+        if (r.selectorText && r.style &&
+          (isExplicitHeight(r.style.getPropertyValue("height")) ||
+            isExplicitHeight(r.style.getPropertyValue("min-height")))) {
+          explicitHeightSelectors.push(r.selectorText);
+        }
+        if (r.selectorText && r.style &&
+          (isExplicitHeight(r.style.getPropertyValue("width")) ||
+            isExplicitHeight(r.style.getPropertyValue("min-width")))) {
+          explicitWidthSelectors.push(r.selectorText);
+        }
       } else if (type === "CSSMediaRule" || type === "CSSSupportsRule") {
-        try { readRules((rule as CSSGroupingRule).cssRules); } catch { /* ignore */ }
+        // Nested grouping rules live in the same sheet — keep the base.
+        try { readRules((rule as CSSGroupingRule).cssRules, base); } catch { /* ignore */ }
       } else if (type === "CSSImportRule") {
+        // The imported sheet is a separate file: its rules resolve against ITS url, falling back to
+        // the importing sheet's base only if the imported sheet reports none.
         const imp = rule as CSSImportRule;
-        try { if (imp.styleSheet) readRules(imp.styleSheet.cssRules); } catch { /* cross-origin */ }
+        try { if (imp.styleSheet) readRules(imp.styleSheet.cssRules, sheetBaseHref(imp.styleSheet) ?? base); } catch { /* cross-origin */ }
       }
     }
   };
 
   for (const sheet of Array.from(document.styleSheets)) {
     try {
-      readRules(sheet.cssRules);
+      readRules(sheet.cssRules, sheetBaseHref(sheet));
     } catch {
       // Cross-origin sheet — record its href so the capture layer can fetch the
       // raw text out-of-band and parse font-faces/urls from it.
@@ -529,6 +747,39 @@ export function collectPage(opts?: { maxNodes?: number } | void): PageSnapshot {
     }
   }
 
+  // Custom elements (web components) carry their styles INSIDE their open shadow root — via
+  // `adoptedStyleSheets` (constructable sheets) and/or `<style>`/`<link>` in the shadow tree
+  // (`shadowRoot.styleSheets`). Those sheets never appear in `document.styleSheets`, so an authored
+  // rule like `color-swatch a { width: 24px }` is invisible to the harvest above and the sizing probe
+  // can't see the explicit width. Walk every open shadow root (composed-tree sweep, matching the
+  // serializer) and read its sheets too — same `readRules` (font-faces, url()s, explicit width/height
+  // selectors). Closed roots return null and are skipped, exactly as elsewhere.
+  const shadowRoots: ShadowRoot[] = [];
+  const collectShadowRoots = (): void => {
+    const stack: Element[] = [];
+    const pushChildren = (parent: Element | Document | ShadowRoot): void => {
+      let c = parent.firstElementChild;
+      while (c) { stack.push(c); c = c.nextElementSibling; }
+    };
+    pushChildren(document);
+    // Depth-first over the composed element tree, descending into every open shadow root.
+    while (stack.length) {
+      const node = stack.pop()!;
+      const sr = (node as HTMLElement).shadowRoot;
+      if (sr) { shadowRoots.push(sr); pushChildren(sr); }
+      pushChildren(node);
+    }
+  };
+  try { collectShadowRoots(); } catch { /* ignore */ }
+  for (const sr of shadowRoots) {
+    const sheets: CSSStyleSheet[] = [];
+    try { sheets.push(...(sr.adoptedStyleSheets || [])); } catch { /* ignore */ }
+    try { sheets.push(...Array.from(sr.styleSheets || [])); } catch { /* ignore */ }
+    for (const sheet of sheets) {
+      try { readRules(sheet.cssRules, sheetBaseHref(sheet)); } catch { if ((sheet as CSSStyleSheet).href) cssUrlSet.add(absUrl((sheet as CSSStyleSheet).href!)); }
+    }
+  }
+
   // CSS custom properties declared on :root.
   try {
     const rootCs = window.getComputedStyle(document.documentElement);
diff --git a/compiler/src/generate/app.ts b/compiler/src/generate/app.ts
index 1a10647..13db98b 100644
--- a/compiler/src/generate/app.ts
+++ b/compiler/src/generate/app.ts
@@ -1,7 +1,7 @@
 import { join } from "node:path";
 import { rmSync } from "node:fs";
 import { writeText } from "../util/fsx.js";
-import type { IR, IRNode, IRChild, IRTextNode } from "../normalize/ir.js";
+import type { IR, IRNode, IRChild, IRTextNode, StyleMap } from "../normalize/ir.js";
 import { isTextChild } from "../normalize/ir.js";
 import { generateCss, RESET_CSS } from "./css.js";
 import { generateInteractionCss } from "./interactionCss.js";
@@ -17,7 +17,7 @@ import { buildClassMap } from "./classMap.js";
 import { buildTailwind, tailwindGlobalsCss } from "./tailwind.js";
 import { planSections, type SectionPlan } from "./sectionSplit.js";
 import type { RecipeReport } from "../infer/recipes.js";
-import { emitSeoAssetFiles, emitSeoRoutes, jsonLdHeadMarkup, metadataExport, routeSummaryFromIr, seoStaticFiles, viewportExport, type SeoInventory } from "./seo.js";
+import { emitSeoAssetFiles, emitSeoRoutes, jsonLdHeadMarkup, metadataExport, routeSummaryFromIr, seoStaticFiles, siteOriginImportLine, SITE_ORIGIN_LAYOUT_IMPORT, SITE_ORIGIN_MODULE, viewportExport, type SeoInventory } from "./seo.js";
 import { emitGeneratedDocs } from "./docs.js";
 
 const VOID_TAGS = new Set(["area", "base", "br", "col", "embed", "hr", "img", "input", "link", "meta", "param", "source", "track", "wbr"]);
@@ -282,6 +282,17 @@ function jsxText(raw: string): string {
   return `{${escapeText(raw)}}`;
 }
 
+/** Collapse a text run under `white-space: normal` the way CSS renders it: every run of
+ *  whitespace (captured \n\t indentation, doubled spaces) becomes a single space, so the
+ *  markup carries content — not the source file's frozen formatting. Leading/trailing single
+ *  spaces are KEPT (JSX-significant for inline flow); the boundary is preserved so `word <b>x</b>`
+ *  keeps its space. A run that is entirely whitespace collapses to a single space. The text gate
+ *  compares whitespace-normalized (gates.ts:normText), so this stays faithful. */
+function collapseWs(raw: string): string {
+  const collapsed = raw.replace(/\s+/g, " ");
+  return collapsed;
+}
+
 /** The ordered [propKey, valueExpr] list a node emits — rendered to clean JSX attributes
  *  by renderAttrs. Each valueExpr is ready-to-emit JS source (a JSON literal,
  *  `true`, or a `{ __html: … }` object). Component extraction reuses this so the
@@ -358,11 +369,20 @@ export function propsList(node: IRNode, assetMap: Map<string, string>, sourceUrl
       if (kept.length === 0) continue;
       value = kept.join(", ");
     } else if (key === "href") {
-      // Preserve in-page anchors. For multi-route sites a linkRewrite maps internal
-      // links to the generated clone routes (and collapsed-collection links to their
-      // representative); otherwise absolutize so it never 404s inside the clone
-      // (external navigation is allowed by the rubric).
-      if (!value.startsWith("#")) value = ctx?.linkRewrite ? ctx.linkRewrite(value) : resolveUrl(value, sourceUrl);
+      // A `javascript:*` href (announcement bars, JS-driven buttons authored as links) is a
+      // script trigger, not a navigable URL. React refuses to render one: it rewrites the
+      // attribute to a long `javascript:throw new Error('React has blocked a javascript: URL…')`
+      // string, which no longer matches the source href in the link gate. The behaviour is
+      // script we don't reproduce anyway, so emit an inert `#` and keep the anchor navigable-inert.
+      if (/^\s*javascript:/i.test(value)) {
+        value = "#";
+      } else if (!value.startsWith("#")) {
+        // Preserve in-page anchors. For multi-route sites a linkRewrite maps internal
+        // links to the generated clone routes (and collapsed-collection links to their
+        // representative); otherwise absolutize so it never 404s inside the clone
+        // (external navigation is allowed by the rubric).
+        value = ctx?.linkRewrite ? ctx.linkRewrite(value) : resolveUrl(value, sourceUrl);
+      }
     }
 
     let reactName = isCustom ? key : (ATTR_RENAME[key] ?? key);
@@ -380,24 +400,44 @@ export function propsList(node: IRNode, assetMap: Map<string, string>, sourceUrl
 
   if (isVideo && !videoLocal && !props.some(([k]) => k === "preload")) props.push(["preload", JSON.stringify("none")]);
 
+  // A canvas emitted as its raster still (<img> — see resolveTag) is decorative
+  // painted surface with no captured alt text; emit alt="" so the img is valid.
+  if (node.tag === "canvas" && node.attrs.src && !props.some(([k]) => k === "alt")) props.push(["alt", JSON.stringify("")]);
+
   if (node.rawHTML && node.tag === "svg") {
     // Strip the Stage-4 capture-id (`data-cid-cap`) the interaction pass stamps on
     // elements: it's internal instrumentation, render-inert, and would otherwise
     // surface verbatim in the markup and (post-extraction) as a bogus data field.
     const inner = svgInnerForNode(node, ctx);
     const svgAttrs = extractSvgAttrs(node.rawHTML);
-    let hasFillAttr = false;
+    let rawFill: string | undefined;
     for (const [k, v] of svgAttrs) {
-      if (k.toLowerCase() === "fill") hasFillAttr = true;
+      if (k.toLowerCase() === "fill") { rawFill = v; continue; } // the root fill is resolved below, not copied verbatim
       if (k === "class" || k === "style" || k === "data-cid-cap" || k.includes(":")) continue;
       const reactName = SVG_ATTR_RENAME[k] ?? k;
       const propKey = /^[a-zA-Z_$][a-zA-Z0-9_$]*$/.test(reactName) ? reactName : JSON.stringify(reactName);
       if (!props.some(([pk]) => pk === propKey)) props.push([propKey, JSON.stringify(v)]);
     }
-    // Raw SVG icons often rely on site CSS (`svg { fill: currentColor }` or a class) that is
-    // stripped during extraction. If the root didn't declare a fill, inherit the surrounding text
-    // color so monochrome wordmarks/icons don't fall back to the browser's black default.
-    if (!hasFillAttr && !props.some(([pk]) => pk === "fill")) props.push(["fill", JSON.stringify("currentColor")]);
+    // Reconcile the root fill against the captured COMPUTED paint. A raw `fill="none"` only looks
+    // unfilled: site CSS (`fill: currentColor` on the wordmark, an inherited color) may actually
+    // paint it, and that CSS is stripped during extraction. resolveSvgRootFill recovers the real
+    // paint — as currentColor when the computed fill tracks the element's color (emit that color
+    // too), else the literal value — and leaves a genuinely unfilled svg as fill="none". When the
+    // root declared no fill at all we fall back to currentColor so monochrome icons don't drop to
+    // the browser's black default.
+    if (!props.some(([pk]) => pk === "fill")) {
+      const resolved = resolveSvgRootFill(rawFill, node.svgPaint);
+      if (resolved.mode === "keep") {
+        if (rawFill !== undefined) props.push(["fill", JSON.stringify(rawFill)]);
+      } else if (resolved.mode === "emit") {
+        props.push(["fill", JSON.stringify(resolved.value!)]);
+        if (resolved.emitColor && !props.some(([pk]) => pk === "color")) {
+          props.push(["color", JSON.stringify(resolved.emitColor)]);
+        }
+      } else {
+        props.push(["fill", JSON.stringify("currentColor")]);
+      }
+    }
     props.push(["dangerouslySetInnerHTML", `{ __html: ${JSON.stringify(inner)} }`]);
   }
 
@@ -445,6 +485,50 @@ function extractSvgAttrs(outerHTML: string): Array<[string, string]> {
   return out;
 }
 
+/** A resolved paint value is "real" (paints something) when it is neither absent nor an explicit
+ * non-paint (`none`) nor fully transparent. `currentColor` counts as real (it paints the inherited
+ * color). Case/whitespace-insensitive. */
+export function isRealPaint(value: string | null | undefined): boolean {
+  const v = (value ?? "").trim().toLowerCase();
+  if (!v || v === "none" || v === "transparent") return false;
+  if (v === "rgba(0, 0, 0, 0)" || v === "rgba(0,0,0,0)") return false;
+  return true;
+}
+
+/**
+ * Decide what `fill` an inline <svg> ROOT should emit, reconciling the raw `fill` attribute against
+ * the svg's COMPUTED paint (captured from the live source). Pure and deterministic.
+ *
+ * - Raw `fill` present and itself a real paint → keep it (`keep`): the author meant that fill.
+ * - Raw `fill="none"` but the computed fill IS a real paint → the root only looked unfilled because
+ *   `fill="none"` is a presentation attribute the site's CSS overrode. Recover the real paint:
+ *   emit `currentColor` when the computed fill equals the computed `color` (a `fill: currentColor`
+ *   class — the common wordmark case; caller must also emit `color`), else the literal computed fill.
+ * - Raw `fill="none"` and computed fill also not a real paint → genuinely unfilled: keep `none`.
+ * - Raw `fill` absent → `fallback`: caller applies its existing currentColor default.
+ */
+export function resolveSvgRootFill(
+  rawFill: string | null | undefined,
+  computed?: { fill?: string; color?: string } | null,
+): { mode: "keep" | "fallback" | "emit"; value?: string; emitColor?: string } {
+  const raw = (rawFill ?? "").trim();
+  if (raw && raw.toLowerCase() !== "none") return { mode: "keep" };
+  if (raw.toLowerCase() === "none") {
+    const cf = computed?.fill;
+    if (isRealPaint(cf)) {
+      const color = (computed?.color ?? "").trim();
+      // fill:currentColor resolves to the element's color; recover it as currentColor so the clone
+      // tracks whatever color the surrounding CSS supplies, and signal the caller to emit that color.
+      if (color && cf!.trim().toLowerCase() === color.toLowerCase() && isRealPaint(color)) {
+        return { mode: "emit", value: "currentColor", emitColor: color };
+      }
+      return { mode: "emit", value: cf!.trim() };
+    }
+    return { mode: "keep" }; // genuinely unfilled — leave fill="none"
+  }
+  return { mode: "fallback" };
+}
+
 // SVG presentation attributes that React requires in camelCase (kebab in JSX is silently
 // dropped — and `fill-rule`/`clip-rule` being dropped changes how a path fills). Anything not
 // here that's already camel/lowercase (d, cx, fill, viewBox, opacity, transform, offset…) or a
@@ -546,6 +630,12 @@ export function resolveTag(node: IRNode, insideInteractive: boolean, insideTable
   // children inside <iframe> are unrendered fallback content, so emit a <div> container
   // carrying the iframe's box/styles (CSS is keyed by cid, so the geometry is identical).
   if (tag === "iframe" && node.children.some((c) => !isTextChild(c))) tag = "div";
+  // A canvas is runtime-drawn surface the clone cannot reproduce; when capture
+  // rasterized it (canvas-still synthetic URL stamped as `src` — see
+  // captureCanvasStillsInPage) emit the still as an <img> filling the canvas's box
+  // (CSS is keyed by cid, so the geometry is identical). A canvas with no still
+  // keeps rendering as an empty <canvas> box, same as before.
+  if (tag === "canvas" && node.attrs.src) tag = "img";
   if (TABLE_SCOPED.has(tag) && !insideTable) tag = "div"; // orphan table element → neutral box
   if (violatesContentModel(node, tag)) tag = "div";
   return tag;
@@ -591,7 +681,7 @@ function renderNode(node: IRNode, assetMap: Map<string, string>, sourceUrl: stri
     return `${pad}<${tag}${attrs} />`;
   }
 
-  const childParts = emitChildren(node.children, tag, assetMap, sourceUrl, indent + 1, childInteractive, ctx, childTable);
+  const childParts = emitChildren(node.children, tag, assetMap, sourceUrl, indent + 1, childInteractive, ctx, childTable, preservesWhitespace(node));
   if (childParts.length === 0) {
     return `${pad}<${tag}${attrs} />`;
   }
@@ -602,7 +692,7 @@ function renderNode(node: IRNode, assetMap: Map<string, string>, sourceUrl: stri
  *  `{Name_data.map(...)}` call for any run of extracted-component instances. Shared
  *  by renderNode (parentTag is the element tag) and the body/chrome fragment
  *  renderers (parentTag null → no element-only-parent whitespace rule). */
-function emitChildren(children: IRChild[], parentTag: string | null, assetMap: Map<string, string>, sourceUrl: string, indent: number, childInteractive: boolean, ctx?: RenderCtx, insideTable = false): string[] {
+function emitChildren(children: IRChild[], parentTag: string | null, assetMap: Map<string, string>, sourceUrl: string, indent: number, childInteractive: boolean, ctx?: RenderCtx, insideTable = false, preserveWs = false): string[] {
   const pad = "  ".repeat(indent);
   const parts: string[] = [];
   // Coalesce consecutive text children into one. Emitting them as separate JSX
@@ -612,7 +702,12 @@ function emitChildren(children: IRChild[], parentTag: string | null, assetMap: M
   let textBuf = "";
   const flushText = () => {
     if (parentTag && ELEMENT_ONLY_PARENTS.has(parentTag) && textBuf.trim() === "") { textBuf = ""; return; }
-    if (textBuf.length) parts.push(`${pad}${jsxText(textBuf)}`);
+    // Under white-space:normal, collapse the captured formatting (\n\t runs, doubled/leading
+    // multi-space) to CSS-equivalent single spaces so markup ships content, not source-file
+    // indentation. A whitespace-only run collapses to a single significant space ({" "}) — the
+    // huge `{"          "}` literals disappear. Preserve verbatim under pre/pre-wrap/pre-line.
+    const out = preserveWs ? textBuf : collapseWs(textBuf);
+    if (out.length) parts.push(`${pad}${jsxText(out)}`);
     textBuf = "";
   };
   const reg = ctx?.components;
@@ -708,12 +803,20 @@ function takeCid(coll: CidCollector, instances: IRNode[]): number {
   return idx;
 }
 
-/** A self-contained class-name merger emitted into each component module that needs it
- *  (kept import-free so component files stay standalone). Skips falsy parts and joins —
- *  exact for our output because a node's baked base classes and its per-instance overrides
- *  are disjoint token sets. Swap in `tailwind-merge` if you want conflict-aware merging
- *  when hand-editing the ./_styles overrides. */
-const CN_HELPER = `function cn(...parts: Array<string | false | null | undefined>) {\n  return parts.filter(Boolean).join(" ");\n}`;
+/** The single shared `cn()` module (`src/lib/utils.ts`), imported by every module that
+ *  merges class names — one definition per clone instead of a copy per component file.
+ *  Skips falsy parts and joins — exact for our output because a node's baked base classes
+ *  and its per-instance overrides are disjoint token sets. Swap in `tailwind-merge` if you
+ *  want conflict-aware merging when hand-editing the ./_styles overrides. */
+export const CN_UTILS_MODULE = `export function cn(...parts: Array<string | false | null | undefined>) {\n  return parts.filter(Boolean).join(" ");\n}\n`;
+
+/** The `import { cn } from "…/lib/utils"` line a module emits when it references `cn(`.
+ *  `depth` is how many directory levels the consuming file sits BELOW `src` (page.tsx in
+ *  `src/app` → 1; a component in `src/app/components` → 2), so the relative path always
+ *  resolves to the single `src/lib/utils`. */
+export function cnImportLine(depth: number): string {
+  return `import { cn } from "${"../".repeat(Math.max(1, depth))}lib/utils";`;
+}
 
 /** Split a className value SOURCE (a JSON string literal as emitted by propsList) into its
  *  whitespace-separated tokens. Returns [] for a non-string / unparseable source. */
@@ -852,6 +955,15 @@ function canonicalViewportFor(n: IRNode): number {
   return keys[0] ?? 1280;
 }
 
+/** Whether a node's `white-space` preserves captured whitespace verbatim (pre/pre-wrap/pre-line/
+ *  break-spaces) — in which case emission must NOT collapse its text runs. `<pre>`/`<textarea>`
+ *  default to pre even without an explicit declaration. Normal/nowrap collapse per CSS. */
+function preservesWhitespace(n: IRNode): boolean {
+  const ws = (n.computedByVp[canonicalViewportFor(n)] ?? Object.values(n.computedByVp)[0])?.whiteSpace;
+  if (ws) return /^(pre|pre-wrap|pre-line|break-spaces)$/.test(ws);
+  return n.tag === "pre" || n.tag === "textarea";
+}
+
 type TextLeaf = { text: string; node: IRNode; index: number; ancestorTags: string[] };
 
 function normalizeTextValue(text: string): string {
@@ -1594,7 +1706,8 @@ export function componentPreamble(reg: ComponentRegistry | undefined): string {
   const cids = reg.cidDecls.map((c) => `const ${c.varName}: string[][] = ${c.body};`);
   const styles = reg.styleDecls.map((s) => `const ${s.varName} = ${s.body};`);
   const fns = [...reg.funcDefs.values()];
-  const cn = fns.some((f) => f.includes("cn(")) ? [CN_HELPER] : [];
+  // Inlined into a chrome module at src/app (layout.tsx) or src/ (Chrome.tsx) — depth 1.
+  const cn = fns.some((f) => f.includes("cn(")) ? [cnImportLine(1)] : [];
   const parts = [...cn, ...fns, ...data, ...cids, ...styles];
   return parts.length ? parts.join("\n\n") : "";
 }
@@ -1818,13 +1931,13 @@ function describeComponent(name: string): string {
   return map[base] ?? `${base.replace(/([a-z])([A-Z])/g, "$1 $2").toLowerCase()} component.`;
 }
 
-export function componentFiles(reg: ComponentRegistry | undefined, svgs?: SvgRegistry): Array<{ name: string; module: string }> {
+export function componentFiles(reg: ComponentRegistry | undefined, svgs?: SvgRegistry, depth = 2): Array<{ name: string; module: string }> {
   if (!reg || reg.funcDefs.size === 0) return [];
   return [...reg.funcDefs].map(([name, src]) => {
     const agg = reg.byName.get(name);
     void agg;
     const header = `/** ${describeComponent(name)} */`;
-    const cnDef = src.includes("cn(") ? CN_HELPER + "\n" : "";
+    const cnImport = src.includes("cn(") ? cnImportLine(depth) : "";
     // The component's props-data type is DEFINED here (colocated), not imported from a central content
     // file — and exported so the section that supplies the data can type its array. Per-instance class
     // overrides still come from _styles.ts (pure styling plumbing).
@@ -1842,9 +1955,9 @@ export function componentFiles(reg: ComponentRegistry | undefined, svgs?: SvgReg
     for (const c of scanRefs(src).comps) {
       if (svgs?.defs.has(c)) svgImports.push(`import ${c} from "../svgs/${svgFileBase(c)}";`);
     }
-    const imports = [...typeImports, ...svgImports];
+    const imports = [...typeImports, ...svgImports, ...(cnImport ? [cnImport] : [])];
     const importBlock = imports.length ? imports.join("\n") + "\n" : "";
-    return { name, module: `${importBlock}${typeDef}${header}\n${cnDef}export default ${src}\n` };
+    return { name, module: `${importBlock}${typeDef}${header}\nexport default ${src}\n` };
   });
 }
 
@@ -2082,6 +2195,7 @@ export function sectionFiles(sreg: SectionRegistry | undefined, reg: ComponentRe
     ];
     const params = paramParts.length ? `{ ${paramParts.join(", ")} } = {}` : "";
     const header = `/** ${describeSection(name)} */`;
+    if (/\bcn\(/.test(body)) lines.push(cnImportLine(2)); // sections live at src/app/sections
     const importBlock = lines.length ? lines.join("\n") + "\n" : "";
     const allConsts = consts;
     const constBlock = allConsts.length ? allConsts.join("\n") + "\n" : "";
@@ -2121,6 +2235,7 @@ export function generatePageTsx(ir: IR, assetMap: Map<string, string>, sourceUrl
     hasMotion ? `import DittoMotion from "${dittoMotionImportPath(0)}";` : "",
     hasLottie ? `import DittoLottie from "${dittoLottieImportPath(0)}";` : "",
     hasMenus ? `import DropdownMenu from "${dropdownMenuImportPath(0)}";` : "",
+    /\bcn\(/.test(body) ? cnImportLine(1) : "", // page.tsx lives at src/app
     ...compImports,
   ].filter(Boolean).join("\n");
   const importBlock = imports ? imports + "\n\n" : "";
@@ -2137,31 +2252,33 @@ ${body}${wiresBlock}${accordionBlock}${motionBlock}${lottieBlock}${menusBlock}
 /** SEO scaffolding (Next App Router): robots.ts + sitemap.ts + an llms.txt route, generated
  *  from the captured URL / title / description — the discovery files a real site ships. */
 function seoFiles(ir: IR): Array<[string, string]> {
-  let origin = "https://example.com";
-  try { origin = new URL(ir.doc.sourceUrl).origin; } catch { /* keep default */ }
-  const url = ir.doc.sourceUrl || origin + "/";
   const title = ir.doc.title || "Home";
   const desc = ir.doc.head?.description || "";
+  // robots.ts / sitemap.ts live at src/app → depth 1 below src. URLs resolve against the
+  // clone's own origin (SITE_ORIGIN, relative by default), never the source domain.
+  const siteImport = siteOriginImportLine(1);
   const robots = `import type { MetadataRoute } from "next";
+${siteImport}
 
 export const dynamic = "force-static";
 
 export default function robots(): MetadataRoute.Robots {
   return {
     rules: { userAgent: "*", allow: "/" },
-    sitemap: ${JSON.stringify(origin + "/sitemap.xml")},
+    sitemap: SITE_ORIGIN + "/sitemap.xml",
   };
 }
 `;
   const sitemap = `import type { MetadataRoute } from "next";
+${siteImport}
 
 export const dynamic = "force-static";
 
 export default function sitemap(): MetadataRoute.Sitemap {
-  return [{ url: ${JSON.stringify(url)}, changeFrequency: "weekly", priority: 1 }];
+  return [{ url: SITE_ORIGIN + "/", changeFrequency: "weekly", priority: 1 }];
 }
 `;
-  const llmsText = [`# ${title}`, ...(desc ? ["", `> ${desc}`] : []), "", "## Pages", "", `- [${title}](${url})`, ""].join("\n");
+  const llmsText = [`# ${title}`, ...(desc ? ["", `> ${desc}`] : []), "", "## Pages", "", `- [${title}](/)`, ""].join("\n");
   const llms = `export const dynamic = "force-static";
 
 export function GET() {
@@ -2183,10 +2300,11 @@ function generateLayoutTsx(ir: IR, bodyClass?: string, seo?: SeoInventory): stri
   const viewport = seo ? viewportExport(seo) : `export const viewport = { width: "device-width", initialScale: 1 };\n`;
   const jsonLd = seo ? jsonLdHeadMarkup(seo, 8) : "";
   const head = jsonLd ? `      <head>\n${jsonLd}\n      </head>\n` : "";
+  const siteImport = seo ? SITE_ORIGIN_LAYOUT_IMPORT + "\n" : "";
   return `import "./globals.css";
 import "./ditto.css";
 import type { ReactNode } from "react";
-
+${siteImport}
 ${metadata}${viewport}
 
 export default function RootLayout({ children }: { children: ReactNode }) {
@@ -2201,10 +2319,36 @@ ${head}      <body${bodyAttrs}>
 `;
 }
 
+const TRANSPARENT_BG = "rgba(0, 0, 0, 0)";
+
+/** Decide what background (if any) the clone's `html` element should paint.
+ *
+ * Per CSS 2.1 §14.2, when `html` is transparent the `body` background propagates
+ * to the canvas and paints *beneath* every descendant — including negative-z-index
+ * layers (full-bleed hero video/image/canvas backdrops). The moment `html` paints
+ * an opaque background, `body` stops propagating and paints its own in-flow block
+ * background, which sits *above* negative-z descendants and buries them.
+ *
+ * So we only give `html` a background when the SOURCE `html` actually painted one.
+ * A transparent source `html` stays transparent (returns null → no rule emitted), so
+ * the captured body background propagates to the canvas exactly as in the source.
+ * The white fallback applies only when BOTH html and body are transparent, otherwise
+ * the UA-default canvas would show through. Deterministic: pure function of the IR. */
+export function resolveHtmlBg(pv: { htmlBg?: string; bodyBg?: string } | undefined): string | null {
+  const srcHtmlBg = pv?.htmlBg && pv.htmlBg !== TRANSPARENT_BG ? pv.htmlBg : null;
+  const srcBodyBg = pv?.bodyBg && pv.bodyBg !== TRANSPARENT_BG ? pv.bodyBg : null;
+  return srcHtmlBg ?? (srcBodyBg ? null : "#ffffff");
+}
+
+/** `html { background: … }` rule, or empty string when html should stay transparent. */
+export function htmlBgRule(htmlBg: string | null): string {
+  return htmlBg !== null ? `html { background: ${htmlBg}; }\n` : "";
+}
+
 function generateGlobalsCss(ir: IR, fontGraph: FontGraph, tokensCss: string): string {
   const cw = ir.doc.canonicalViewport;
   const pv = ir.doc.perViewport[cw];
-  const htmlBg = pv?.htmlBg && pv.htmlBg !== "rgba(0, 0, 0, 0)" ? pv.htmlBg : (pv?.bodyBg ?? "#ffffff");
+  const htmlBg = resolveHtmlBg(pv);
   // If the SOURCE page never scrolls horizontally (its scrollWidth fits the
   // viewport at every captured width), neither should the clone. JS-driven
   // widgets (custom-element carousels, sliders) position children off-axis via
@@ -2222,8 +2366,7 @@ ${fontGraph.css}
 ${tokensCss}
 
 /* page base */
-html { background: ${htmlBg}; }
-body { font-family: ${SYSTEM_FALLBACK}; }${clip}
+${htmlBgRule(htmlBg)}body { font-family: ${SYSTEM_FALLBACK}; }${clip}
 `;
 }
 
@@ -2345,17 +2488,113 @@ ${input}
 `;
 }
 
-function recipeResponsiveClassCleaner(recipes: RecipeReport | undefined, opts: { tailwind: boolean }): (cid: string, className: string | undefined) => string | undefined {
+// Number of explicit column tracks in a computed `grid-template-columns` value. The capture
+// resolves the property to a used track list (e.g. `284px 284px 284px`), so track count is the
+// whitespace-separated token count; `none`/empty means the element is not a track grid.
+function computedTrackCount(value: string | undefined): number {
+  if (!value || value === "none") return 0;
+  return value.trim().split(/\s+/).filter(Boolean).length;
+}
+
+// Resolved px widths of the explicit column tracks in a computed `grid-template-columns` value. The
+// capture resolves the property to a used track list (`260px 1020px`), so each token is a definite
+// px length. Non-px tokens (`auto`, `min-content`, a leftover `1fr`) make the track set unquantifiable
+// and yield null — the plan then cannot claim the tracks are uniform.
+function computedTrackWidths(value: string | undefined): number[] | null {
+  if (!value || value === "none") return null;
+  const toks = value.trim().split(/\s+/).filter(Boolean);
+  const out: number[] = [];
+  for (const t of toks) {
+    const m = /^(-?\d*\.?\d+)px$/.exec(t);
+    if (!m) return null;
+    out.push(parseFloat(m[1]!));
+  }
+  return out.length ? out : null;
+}
+
+// A `grid-cols-N` plan rewrites the container to `repeat(N, minmax(0, 1fr))` — N EQUAL tracks. It is
+// only a faithful replacement for the authored template when the computed tracks actually are ~equal
+// width. An asymmetric template (`260px 1fr` → a 260/1020 sidebar layout) has the same track COUNT as
+// the heuristic column count but a different geometry; collapsing it to equal halves destroys the
+// authored layout, so such templates always keep their computed tracks.
+function tracksNearEqual(widths: number[]): boolean {
+  if (widths.length <= 1) return true;
+  const max = Math.max(...widths);
+  const min = Math.min(...widths);
+  if (!(max > 0)) return false;
+  // Tolerance: a couple of px (gap/rounding) or 2% of the widest track, whichever is larger.
+  return max - min <= Math.max(1.5, 0.02 * max);
+}
+
+// Track span of a grid item from its resolved `grid-column-start`/`grid-column-end`. A spanning
+// item (`span 2`, or an explicit line pair `1 / 3`) means row-length item-counting under-reports
+// the real track count, so the column-count heuristic is not trustworthy for this container.
+function computedColumnSpan(cs: StyleMap | undefined): number {
+  if (!cs) return 1;
+  const end = cs["gridColumnEnd"];
+  const start = cs["gridColumnStart"];
+  const span = /^span\s+(\d+)$/.exec(end ?? "") ?? /^span\s+(\d+)$/.exec(start ?? "");
+  if (span) return Math.max(1, Number(span[1]));
+  if (start && end && /^-?\d+$/.test(start) && /^-?\d+$/.test(end)) {
+    const diff = Number(end) - Number(start);
+    if (Number.isFinite(diff) && diff > 1) return diff;
+  }
+  return 1;
+}
+
+export function recipeResponsiveClassCleaner(ir: IR, recipes: RecipeReport | undefined, opts: { tailwind: boolean }): (cid: string, className: string | undefined) => string | undefined {
   const recipeParents = new Set<string>();
   const repeatedGridParents = new Set<string>();
   const fillGridParents = new Set<string>();
+  // Containers whose computed geometry agreed with the item-count heuristic — a genuinely uniform
+  // repeated grid the recipe may re-flow. Row-track utilities are only stripped here; on containers
+  // where the geometry disagreed (spanning items / differing track count) the authored row and
+  // column tracks are ground truth and must survive.
+  const uniformGridParents = new Set<string>();
   const columnPlans = new Map<string, string[]>();
+  const nodeByCid = new Map<string, IRNode>();
+  const index = (n: IRNode): void => { nodeByCid.set(n.id, n); for (const c of n.children) if (!isTextChild(c)) index(c); };
+  index(ir.root);
+  // The captured/computed grid geometry is ground truth. A recipe may add semantic structure, but
+  // its column count is inferred by grouping item bounding boxes into rows — which under-reports the
+  // real track count whenever an item spans multiple columns. Before letting a recipe's synthesized
+  // column plan override the authored grid, cross-check it against the computed `grid-template-columns`
+  // track count and per-item `grid-column` spans at each regime viewport. On disagreement, keep the
+  // emitted (computed) geometry and drop the plan so spans and track count survive.
+  const planAgreesWithComputed = (c: RecipeReport["candidates"][number], regimeVps: number[]): boolean => {
+    const parent = c.itemParentCid ? nodeByCid.get(c.itemParentCid) : undefined;
+    if (!parent) return false;
+    const itemCids = (c.repeatedItems ?? []).map((i) => i.cid);
+    for (const vp of regimeVps) {
+      const gtc = parent.computedByVp[vp]?.["gridTemplateColumns"];
+      const tracks = computedTrackCount(gtc);
+      // Only trust the heuristic where the computed grid actually is a track grid at this viewport.
+      if (tracks === 0) continue;
+      const regime = c.responsiveRegimes.find((r) => r.viewport === vp);
+      const heuristicCols = regime?.columns ?? 0;
+      if (heuristicCols > 0 && heuristicCols !== tracks) return false;
+      // A `grid-cols-N` plan means N EQUAL tracks. If the computed tracks are asymmetric (a sidebar
+      // template like `260px 1020px`), the count agrees but the geometry does not — collapsing to
+      // equal columns would destroy the authored layout. Keep the authored template in that case.
+      if (tracks >= 2) {
+        const widths = computedTrackWidths(gtc);
+        if (!widths || !tracksNearEqual(widths)) return false;
+      }
+      for (const cid of itemCids) {
+        if (computedColumnSpan(nodeByCid.get(cid)?.computedByVp[vp]) > 1) return false;
+      }
+    }
+    return true;
+  };
   const gridColumnTokens = (c: RecipeReport["candidates"][number]): string[] | null => {
     if (c.kind !== "card-grid" && c.kind !== "feature-grid" && c.kind !== "product-grid") return null;
     const regimes = c.responsiveRegimes
       .filter((r) => (r.visibleItems ?? 0) > 0 && (r.columns ?? 0) > 0)
       .sort((a, b) => a.viewport - b.viewport);
     if (regimes.length < 2) return null;
+    // The computed track geometry disagrees with the item-count heuristic (spanning items or a
+    // differing track count) — defer to the authored grid rather than synthesize a column plan.
+    if (!planAgreesWithComputed(c, regimes.map((r) => r.viewport))) return null;
     const prefixFor = (vp: number): string => vp >= 1536 ? "2xl:" : vp >= 1024 ? "lg:" : vp >= 768 ? "md:" : "";
     const tokens: string[] = [];
     let last: number | undefined;
@@ -2377,6 +2616,12 @@ function recipeResponsiveClassCleaner(recipes: RecipeReport | undefined, opts: {
   for (const c of recipes?.candidates ?? []) {
     if ((c.kind === "card-grid" || c.kind === "feature-grid" || c.kind === "product-grid" || c.kind === "gallery-showcase" || c.kind === "logo-cloud") && c.confidence >= 0.86 && c.itemParentCid) {
       recipeParents.add(c.itemParentCid);
+      // A container is a uniform repeated grid only if its computed track geometry agrees with the
+      // item-count heuristic at every sampled regime viewport (no spanning items, matching track
+      // count). Non-grid containers (flex/stack) have no computed tracks to disagree with, so they
+      // stay eligible; a track grid whose geometry disagrees is excluded and keeps its authored rows.
+      const sampledVps = c.responsiveRegimes.map((r) => r.viewport);
+      if (planAgreesWithComputed(c, sampledVps)) uniformGridParents.add(c.itemParentCid);
       if (c.kind === "card-grid" || c.kind === "feature-grid" || c.kind === "product-grid" || c.kind === "gallery-showcase") repeatedGridParents.add(c.itemParentCid);
       if (c.kind === "card-grid" || c.kind === "feature-grid" || c.kind === "product-grid") fillGridParents.add(c.itemParentCid);
       const columns = gridColumnTokens(c);
@@ -2390,8 +2635,8 @@ function recipeResponsiveClassCleaner(recipes: RecipeReport | undefined, opts: {
     const columnPlan = opts.tailwind ? columnPlans.get(cid) : undefined;
     const keep = tokens.filter((token) => {
       if (columnPlan && /^(?:[a-z0-9-]+:)*grid-cols-(?:\d+|\[[^\]]+\])$/.test(token)) return false;
-      if (/^(?:[a-z0-9-]+:)*grid-rows-\[(?:auto_?)+\]$/.test(token)) return false;
-      if (repeatedGridParents.has(cid) && /^(?:[a-z0-9-]+:)*grid-rows-\d+$/.test(token)) return false;
+      if (uniformGridParents.has(cid) && /^(?:[a-z0-9-]+:)*grid-rows-\[(?:auto_?)+\]$/.test(token)) return false;
+      if (uniformGridParents.has(cid) && repeatedGridParents.has(cid) && /^(?:[a-z0-9-]+:)*grid-rows-\d+$/.test(token)) return false;
       const initialCols = /^(?:(.*):)?grid-cols-\[initial\]$/.exec(token);
       if (initialCols) {
         const prefix = initialCols[1] ? `${initialCols[1]}:` : "";
@@ -2436,9 +2681,12 @@ export function generateApp(input: GenerateInput, tokensCss: string): { pageTsx:
   const mode = input.humanizeMode ?? "tailwind";
   // Tailwind mode (default): translate each node's exact decls to utility classes.
   // CSS mode: dedup into shared semantic CSS classes. Both fidelity-neutral.
-  const tw = humanize && mode === "tailwind" ? buildTailwind(ir, assetMap, input.colorVar, { interaction: input.interaction, reflow: input.reflow }) : undefined;
+  // Lottie mount boxes are pinned to their captured height (replaced-like) so the runtime player's
+  // aspect-sized svg fills a definite box instead of inflating. The spec item cid IS the mount cid.
+  const lottieMounts = new Set(lottieSpec.items.map((it) => it.cid));
+  const tw = humanize && mode === "tailwind" ? buildTailwind(ir, assetMap, input.colorVar, { interaction: input.interaction, reflow: input.reflow, lottieMounts }) : undefined;
   const classMap = humanize && mode === "css" ? buildClassMap(ir, assetMap, input.colorVar, input.primitives, input.tokenResolver) : undefined;
-  const cleanRecipeClass = recipeResponsiveClassCleaner(input.recipeReport, { tailwind: !!tw });
+  const cleanRecipeClass = recipeResponsiveClassCleaner(ir, input.recipeReport, { tailwind: !!tw });
   const classOf = tw ? (cid: string) => cleanRecipeClass(cid, tw.classOf.get(cid)) : classMap ? (cid: string) => classMap.classOf.get(cid) : undefined;
   const styleOf = tw ? (cid: string) => tw.styleOf.get(cid) : undefined;
   // Section split (single-page humanized): plan section roots, render each into its own
@@ -2527,7 +2775,7 @@ export function generateApp(input: GenerateInput, tokensCss: string): { pageTsx:
   if (tw) {
     const cw = ir.doc.canonicalViewport;
     const pv = ir.doc.perViewport[cw];
-    const htmlBg = pv?.htmlBg && pv.htmlBg !== "rgba(0, 0, 0, 0)" ? pv.htmlBg : (pv?.bodyBg ?? "#ffffff");
+    const htmlBg = resolveHtmlBg(pv);
     const noHScroll = Object.entries(ir.doc.perViewport).every(([vp, d]) => d.scrollWidth <= Number(vp) * 1.03);
     const clip = noHScroll ? "\nhtml, body { overflow-x: clip; }" : "";
     const globals = tailwindGlobalsCss({
@@ -2541,6 +2789,9 @@ export function generateApp(input: GenerateInput, tokensCss: string): { pageTsx:
     writeText(join(rootDir, "globals.css"), framework === "vite" ? viteGlobalsCss(globals) : globals);
   }
   writeText(join(rootDir, "ditto.css"), cloneCss);
+  writeText(join(appDir, "src", "lib", "utils.ts"), CN_UTILS_MODULE);
+  // SITE_ORIGIN constant for SEO/metadata routes (Next only — Vite ships static SEO files).
+  if (framework === "next") writeText(join(appDir, "src", "lib", "site.ts"), SITE_ORIGIN_MODULE);
   if (wires.length) writeText(join(rootDir, "ditto", "DittoWire.tsx"), DITTO_WIRE_TSX);
   if (accordions.length) writeText(join(rootDir, "ditto", "Accordion.tsx"), ACCORDION_TSX);
   if (motionHasContent(motionSpec)) writeText(join(rootDir, "ditto", "DittoMotion.tsx"), DITTO_MOTION_TSX);
diff --git a/compiler/src/generate/css.ts b/compiler/src/generate/css.ts
index 2730540..74eb531 100644
--- a/compiler/src/generate/css.ts
+++ b/compiler/src/generate/css.ts
@@ -1,5 +1,5 @@
 import type { IR, IRNode, StyleMap } from "../normalize/ir.js";
-import { isTextChild } from "../normalize/ir.js";
+import { isTextChild, irContentExtent } from "../normalize/ir.js";
 import type { TokenResolver } from "../infer/tokens.js";
 
 /** Finalize a decls map: reference design tokens (var(--…)) where the value is tokenized
@@ -32,6 +32,11 @@ button, input, select, textarea, optgroup { font: inherit; color: inherit; backg
 button { cursor: pointer; }
 table { border-collapse: separate; border-spacing: 0; }
 img, picture, video, canvas, svg { display: inline-block; }
+/* Lottie runtime fit: the player re-mounts its svg/canvas into an absolute overlay that fills
+   the host's captured (per-viewport, definite) box. Force that runtime media to fit the box so
+   an aspect-mismatched viewBox (e.g. a portrait animation in a shorter, letterboxed source box)
+   can't inflate past the pinned height. Scoped to the runtime-marked host only. */
+[data-ditto-lottie] > div > svg, [data-ditto-lottie] > div > canvas { width: 100%; height: 100%; display: block; }
 h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd { margin: 0; }
 /* Neutralize UA text defaults to inherit so the generator's default-skipping is
    correct: a property equal to its inherited value is simply not emitted. */
@@ -69,7 +74,7 @@ function isViewportHeight(value: string, width: number): boolean {
 const INHERITED = new Set([
   "color", "fontFamily", "fontSize", "fontWeight", "fontStyle", "lineHeight",
   "letterSpacing", "wordSpacing", "textAlign", "textTransform", "whiteSpace",
-  "wordBreak", "overflowWrap", "textIndent", "fontVariantCaps", "fontFeatureSettings",
+  "wordBreak", "overflowWrap", "textWrap", "textIndent", "fontVariantCaps", "fontFeatureSettings",
   "listStyleType", "listStylePosition", "writingMode", "direction", "cursor",
   "textShadow", "visibility", "textDecorationColor", "webkitTextStroke",
   "webkitTextFillColor",
@@ -134,6 +139,8 @@ const GENERIC: Array<{ prop: string; def: string | string[] }> = [
   { prop: "textDecorationStyle", def: "solid" },
   { prop: "whiteSpace", def: "__never__" }, { prop: "wordBreak", def: "__never__" },
   { prop: "overflowWrap", def: "__never__" }, { prop: "textIndent", def: "__never__" },
+  // text-wrap: elide the initial `wrap`; emit `balance`/`pretty`/`nowrap`/`stable`.
+  { prop: "textWrap", def: "wrap" },
   { prop: "textShadow", def: "__never__" }, { prop: "fontVariantCaps", def: "__never__" },
   { prop: "fontFeatureSettings", def: "__never__" }, { prop: "listStyleType", def: "__never_list__" },
   { prop: "listStylePosition", def: "__never__" }, { prop: "writingMode", def: "__never__" },
@@ -237,9 +244,13 @@ function isFluidFullBleed(node: IRNode, parentNode: IRNode | undefined, viewport
     const pos = cs.position || "static";
     if (pos === "absolute" || pos === "fixed") {
       if (!(nearZero(cs.left) && nearZero(cs.right))) return false; // width is real unless both insets pin it
-    } else if (pos === "sticky") {
-      return false;
     } else {
+      // static | relative | sticky. A sticky box generates a normal in-flow box: its WIDTH fills the
+      // containing block exactly as static/relative does (position:sticky only shifts the box's offset
+      // while scrolling, never its resolved width). So a sticky wrapper that spans the viewport at
+      // every captured width was authored fluid (width:100%/auto) and must NOT freeze to the canonical
+      // px — frozen at 1280, a `justify-content:center` sticky banner pushes its inner content off a
+      // 375 viewport. Treat sticky identically to the static/relative fluid-fill branch.
       if (!(zeroOrAuto(cs.left) && zeroOrAuto(cs.right))) return false; // positioned breakout: width is real
       const pdisp = parentNode?.computedByVp[vp]?.display || "";
       if (/flex|grid/.test(pdisp)) return false; // flex/grid item: auto width ≠ fill
@@ -298,12 +309,16 @@ export type WidthPlan = { kind: "fixed" } | { kind: "auto" } | { kind: "percent"
 const PLAN_FIXED: WidthPlan = { kind: "fixed" };
 
 const pf = (v: string | undefined): number => { const n = parseFloat(v ?? ""); return Number.isFinite(n) ? n : 0; };
-const fmtPx = (n: number): string => `${Math.round(n * 1000) / 1000}px`;
+// Snap sub-pixel geometry: integer when within 0.1px (measurement jitter), else at most 1 decimal
+// — matching the Tailwind arbitrary-length rounding (tailwind.ts:snapLen) so CSS and utility output
+// agree and frozen sub-pixel noise (204.797px) never ships. Transforms/border widths format elsewhere.
+const fmtPx = (n: number): string => `${(Math.abs(n - Math.round(n)) < 0.1 ? Math.round(n) : Math.round(n * 10) / 10)}px`;
 const viewportHeightFor = (vp: number): number => CAPTURE_VIEWPORT_HEIGHTS[vp] ?? Math.round(vp * 0.66);
 
 type GeometryPlan = {
   heightByVp?: Record<number, string>;
   aspectByVp?: Record<number, string>;
+  minHeightByVp?: Record<number, string>;
   leftByVp?: Record<number, string>;
   topByVp?: Record<number, string>;
 };
@@ -354,11 +369,17 @@ function planWidth(node: IRNode, parentNode: IRNode | undefined, viewports: numb
   // Replaced/custom elements size to intrinsic dimensions under auto/%, not the container.
   if (REPLACED.has(node.tag) || node.tag.includes("-")) return none;
 
-  type Sample = { w: number; bw: number; cw: number; ml: number; mr: number; maxW: number | null; gapL: number; gapR: number; borderBox: boolean };
+  type Sample = { w: number; bw: number; cw: number; ml: number; mr: number; maxW: number | null; gapL: number; gapR: number; borderBox: boolean; visible: boolean };
   const samples: Sample[] = [];
   for (const vp of viewports) {
     const cs = node.computedByVp[vp]; const nb = node.bboxByVp[vp];
     if (!cs || !nb) continue;
+    // A viewport where the node (or its containing block) is display:none / zero-box contributes no
+    // geometry: its computed box is 0×0, margins report the unresolved `auto`, and the containing width
+    // is 0. Skip it rather than bailing the whole inference — a container hidden at some breakpoints can
+    // still be provably centred at the widths where it IS painted (judged over the visible samples below).
+    const paintedHere = !!node.visibleByVp[vp] && nb.width > 0;
+    if (!paintedHere) continue;
     // Block-LEVEL, in-flow only: margin-auto centring and auto/100% fill apply to these; an
     // inline / inline-block / flex-item box is positioned differently, so bail conservatively.
     if (!/^(block|flow-root|list-item|flex|grid)$/.test(cs.display || "")) return none;
@@ -379,6 +400,7 @@ function planWidth(node: IRNode, parentNode: IRNode | undefined, viewports: numb
     samples.push({
       w, bw: nb.width, cw, ml: pf(cs.marginLeft), mr: pf(cs.marginRight), maxW,
       gapL: nb.x - cl, gapR: cr - (nb.x + nb.width), borderBox: (cs.boxSizing || "border-box") !== "content-box",
+      visible: !!node.visibleByVp[vp] && nb.width > 0,
     });
   }
   if (samples.length < 2) return none;
@@ -387,14 +409,26 @@ function planWidth(node: IRNode, parentNode: IRNode | undefined, viewports: numb
   const span = (xs: number[]): number => Math.max(...xs) - Math.min(...xs);
   const zeroMargins = samples.every((s) => Math.abs(s.ml) <= 1.5 && Math.abs(s.mr) <= 1.5);
 
-  // (a) Centred max-width container: border-box, a single px max-width cap, and every sample's
-  // border box equals min(containerWidth, cap) — filling when narrower than the cap, centred
-  // (symmetric positive gaps) when wider. Reproduces `max-width:W; margin:0 auto` exactly.
-  if (samples.every((s) => s.maxW != null && s.borderBox)) {
-    const caps = samples.map((s) => s.maxW!);
-    let ok = span(caps) <= Math.max(2, 0.01 * Math.max(...caps));
+  // (a) Centred max-width container: border-box, a px max-width cap AT EVERY sample, and every
+  // sample's border box equals min(containerWidth, cap) — filling when narrower than the cap, centred
+  // (symmetric positive gaps) when wider. Reproduces `margin:0 auto` centring with a per-viewport cap.
+  // The cap need NOT be a single constant: a fluid `max-width: min(Wpx, 100vw − 2·gutter)` resolves to
+  // a DIFFERENT px per width (e.g. 311/673/1145/1272), so requiring a constant cap wrongly rejected the
+  // commonest centred container and left it PLAN_FIXED with literal per-band `mx-*` (off-centre at any
+  // non-captured width). We accept per-viewport caps and let the normal per-band `max-width` emission
+  // carry them; `mx-auto` (from centerAlways) then centres at EVERY width. Fidelity is preserved
+  // because each sample's `min(cw, maxW_vp)` reproduces the captured box exactly at that width. The
+  // `sawCenter` requirement below is the load-bearing guard: a box that merely FILLS (never shows
+  // symmetric free-space gaps) is NOT proven centred and stays PLAN_FIXED with its literal margins.
+  // A display:none / zero-box sample has no geometry to prove centring against (its computed box is
+  // 0×0 and its margins report the unresolved `auto`). Judge case (a) only over the VISIBLE samples —
+  // a container centred wherever it is actually painted is centred everywhere via `mx-auto`, even if it
+  // is hidden at some breakpoints. (≥2 visible samples still required so the inference has evidence.)
+  const vis = samples.filter((s) => s.visible);
+  if (vis.length >= 2 && vis.every((s) => s.maxW != null && s.borderBox)) {
+    let ok = true;
     let sawCenter = false;
-    if (ok) for (const s of samples) {
+    for (const s of vis) {
       if (!close(s.bw, Math.min(s.cw, s.maxW!), 1.5, 0.01)) { ok = false; break; }
       if (s.cw > s.maxW! + 4) { // room to centre — must actually be centred, not left-aligned
         if (s.gapL > 1 && s.gapR > 1 && Math.abs(s.gapL - s.gapR) <= 1.5) sawCenter = true;
@@ -780,6 +814,69 @@ function singleFluidGridRow(node: IRNode, viewports: number[]): Map<number, stri
   return painted >= 2 ? result : null;
 }
 
+/** A box authored with a viewport-relative min-height (e.g. `min-h-screen` or
+ * `min-h-[calc(100vh - Cpx)]`) whose per-viewport px is baked at capture, freezing a full-screen
+ * hero to one window height. The engine only sees the resolved px, so we recover the authored law
+ * `calc(100vh - Cpx)` (constant offset C, k=1) from samples spanning DIFFERENT viewport heights and
+ * re-emit it as a viewport unit. Gated by an authored vh-token corroboration so a content-driven
+ * min-height can't be mistaken for a viewport law. */
+function viewportMinHeightLaw(node: IRNode, viewports: number[]): Record<number, string> | null {
+  // Authored corroboration: only recover a viewport law when the source class carries a
+  // viewport-relative min-height intent. Without srcClass we can't distinguish it from a fixed box.
+  const src = node.srcClass || "";
+  if (!src) return null;
+  const hasVhIntent =
+    /\b\d*\.?\d*(?:vh|dvh|svh|lvh)\b/.test(src) ||
+    src.includes("100vh") || src.includes("min-h-screen") ||
+    src.includes("min-h-[100vh") || src.includes("calc(100vh");
+  if (!hasVhIntent) return null;
+
+  const samples: Array<{ vp: number; mh: number; vh: number }> = [];
+  for (const vp of viewports) {
+    const cs = node.computedByVp[vp]; const nb = node.bboxByVp[vp];
+    if (!cs || !nb || !node.visibleByVp[vp] || (cs.display || "") === "none") continue;
+    const mhRaw = cs.minHeight;
+    if (!mhRaw || !mhRaw.endsWith("px")) continue;
+    const mh = pf(mhRaw);
+    if (!(mh >= 120)) continue; // avoid tiny content boxes
+    samples.push({ vp, mh, vh: viewportHeightFor(vp) });
+  }
+  if (samples.length < 2) return null;
+  // The law must be DETERMINED: at least two samples whose viewport heights actually differ.
+  // If every sample shares one viewport height, a fixed px is indistinguishable from `100vh`.
+  const vhs = samples.map((s) => s.vh);
+  if (Math.max(...vhs) - Math.min(...vhs) <= 1) return null;
+
+  // Per-sample offset C_i = vh_i - mh_i, checked against the SAME viewport's own captured height (an
+  // exact per-sample identity, not an extrapolation). Responsive heroes are commonly authored as a
+  // BREAKPOINT-SPLIT law — `min-h-[100vh] md:min-h-[calc(100vh - Cpx)]` — so C is a per-regime
+  // constant, NOT globally constant: the mobile band has C≈0 (`100vh`) while the desktop bands share
+  // one positive C (`calc(100vh - Cpx)`). We allow that split but keep each regime determined:
+  //   - each C_i must be a modest subtraction (0 <= C_i <= 0.5·vh_i), else the box isn't viewport-fit;
+  //   - the NON-ZERO offsets must all agree within 1.5px (one determined desktop offset, k=1) — a
+  //     spread of distinct positive C's is ambiguous, so bail rather than freeze a wrong law.
+  const offsets = samples.map((s) => ({ vp: s.vp, c: s.vh - s.mh, vh: s.vh }));
+  for (const o of offsets) {
+    if (o.c < -1.5) return null;              // an addition, not a viewport-fit subtraction
+    if (o.c > 0.5 * o.vh) return null;        // too large an offset to be a full-screen hero
+  }
+  const nonZero = offsets.filter((o) => o.c > 1.5).map((o) => o.c);
+  let deskC = 0;
+  if (nonZero.length) {
+    // A non-zero offset regime must be CORROBORATED: a lone desktop sample with a unique positive C is
+    // indistinguishable from a genuinely fixed px min-height (e.g. `min-h-[100vh] md:min-h-[500px]`), so
+    // require >= 2 desktop samples that agree on one C (within 1.5px). A C≈0 (`100vh`) band is an exact
+    // per-sample viewport identity and needs no such corroboration.
+    if (nonZero.length < 2) return null;
+    const mean = nonZero.reduce((a, b) => a + b, 0) / nonZero.length;
+    if (nonZero.some((c) => Math.abs(c - mean) > 1.5)) return null; // desktop offsets disagree
+    deskC = Math.round(mean);
+  }
+  const out: Record<number, string> = {};
+  for (const o of offsets) out[o.vp] = o.c <= 1.5 ? "100vh" : `calc(100vh - ${deskC}px)`;
+  return out;
+}
+
 /** A large structural/media box whose captured height is a viewport-height expression with a lower
  * and/or upper clamp. Cursor's demo frames are the canonical example: every sampled height equals
  * `clamp(MIN, 70vh, MAX)`, but the engine only sees the resolved px row height. */
@@ -853,7 +950,15 @@ function aspectHeightLaw(node: IRNode, viewports: number[]): Record<number, stri
     let chosen: { value: string; ratio: number } | undefined;
     for (const r of ordered) {
       const predicted = Math.min(s.w / r.ratio, s.maxH);
-      if (Math.abs(predicted - s.h) <= Math.max(1.5, 0.01 * s.h)) { chosen = r; break; }
+      if (Math.abs(predicted - s.h) > Math.max(1.5, 0.01 * s.h)) continue;
+      // Aspect-ratio + max-height also transfers into a max-WIDTH: per CSS transferred sizing, a box
+      // with `aspect-ratio:R` and `max-height:M` cannot exceed `R × M` wide (the height cap back-computes
+      // a width cap). The height-only check above accepts any ratio that makes min(w/R, M) ≈ h at a
+      // clamped viewport, but a ratio whose transferred max-width (R × M) is narrower than the measured
+      // box would clamp the clone's width below the source (a 1.66:1 box forced square to its 420px cap).
+      // Require the measured width to fit under the transferred cap at every clamped sample.
+      if (Number.isFinite(s.maxH) && s.w > r.ratio * s.maxH + Math.max(1.5, 0.01 * s.w)) continue;
+      chosen = r; break;
     }
     if (!chosen) return null;
     out[s.vp] = chosen.value;
@@ -864,6 +969,24 @@ function aspectHeightLaw(node: IRNode, viewports: number[]): Record<number, stri
   return out;
 }
 
+/** A lottie mount box: the container the runtime player re-mounts its svg/canvas into. The player
+ * sizes that svg by the animation's aspect at the container's width, so without a pinned height the
+ * mount inflates to the aspect height (overlapping neighbours). Treat it as replaced-like — pin the
+ * captured per-viewport border-box height (the source-constrained size) so the aspect-fit svg fills
+ * a definite box. Per viewport, like img/video height emission. */
+function lottieMountHeight(node: IRNode, viewports: number[]): Record<number, string> | null {
+  const out: Record<number, string> = {};
+  let any = false;
+  for (const vp of viewports) {
+    const nb = node.bboxByVp[vp];
+    if (!nb || !node.visibleByVp[vp] || (node.computedByVp[vp]?.display || "") === "none") continue;
+    if (!(nb.height > 0)) continue;
+    out[vp] = fmtPx(nb.height);
+    any = true;
+  }
+  return any ? out : null;
+}
+
 function mediaHeightGeometry(node: IRNode, viewports: number[]): Pick<GeometryPlan, "heightByVp" | "aspectByVp"> {
   const heightByVp = viewportHeightLaw(node, viewports);
   if (heightByVp) return { heightByVp };
@@ -966,6 +1089,22 @@ function isFlexFillItem(node: IRNode, parentNode: IRNode | undefined, viewports:
  *  genuine circular collapse, never on a normal content-sized shrink-0 item. */
 function isCircularShrinkSlide(node: IRNode, parentNode: IRNode | undefined, viewports: number[]): boolean {
   if (!parentNode || REPLACED.has(node.tag) || node.tag.includes("-")) return false;
+  // A box that spans the full viewport at ≥2 distinct widths with no horizontal margins has a real
+  // width source (it fills a fluid container / was authored width:100%) — it is NOT a circular-collapse
+  // slide. `width:100%`/`auto` gives its fill-children a valid definite basis, so there is nothing to
+  // collapse. Same "proven fluid" bar (samples >= 2 distinct widths) used by isFluidFullBleed /
+  // isFluidFillItem above; freezing such a full-bleed section to captured px is exactly the misfire.
+  const nearZero = (v: string | undefined): boolean => v != null && v !== "auto" && Math.abs(parseFloat(v)) <= 1.5;
+  let fluidSpan = 0;
+  for (const vp of viewports) {
+    const cs = node.computedByVp[vp]; const bb = node.bboxByVp[vp];
+    if (!cs || !bb || !node.visibleByVp[vp] || (cs.display || "") === "none" || !(bb.width > 0)) continue;
+    if (Math.abs(bb.x) > 1.5) continue;                  // must start at the left edge
+    if (Math.abs(bb.width - vp) > 1.5) continue;         // must span the full viewport
+    if (!nearZero(cs.marginLeft) || !nearZero(cs.marginRight)) continue; // margins make the width load-bearing
+    fluidSpan++;
+  }
+  if (fluidSpan >= 2) return false;                       // proven fluid full-bleed, not a circular slide
   let painted = 0;
   for (const vp of viewports) {
     const cs = node.computedByVp[vp]; const pcs = parentNode.computedByVp[vp]; const nb = node.bboxByVp[vp];
@@ -987,7 +1126,16 @@ function isCircularShrinkSlide(node: IRNode, parentNode: IRNode | undefined, vie
       const cpos = ccs.position || "static";
       if (cpos === "absolute" || cpos === "fixed") continue;                // out of flow → no width contribution
       const csz = c.sizingByVp?.[vp];
-      if (csz && csz.wFill === true && csz.wAuto === false) { fillChildren++; continue; } // fills the slide → derives width from it
+      // A block-level in-flow box (block/flex/grid/table/list-item) takes its width FROM its
+      // container by definition: its `width:auto` computed size IS the fill size, so the probe
+      // reports wAuto AND wFill both true — indistinguishable from a genuine content-sized source.
+      // Such a child still DERIVES its width from the slide (it never establishes one), so it must
+      // count as a fill child, not veto the circular case. Only wFill matters for a block child;
+      // wAuto is redundant with it. Inline / inline-block children (whose auto width is genuinely
+      // content-derived and can size the slide) keep the strict wFill && !wAuto test.
+      const cDisp = ccs.display || "";
+      const blockLevel = /^(block|flex|grid|table|list-item|flow-root)$/.test(cDisp);
+      if (csz && csz.wFill === true && (blockLevel || csz.wAuto === false)) { fillChildren++; continue; } // fills/derives width from the slide
       return false;                                                         // a genuine in-flow width source → not circular
     }
     if (fillChildren === 0) return false;
@@ -1113,6 +1261,100 @@ function sourceFixedSizeIntent(node: IRNode): boolean {
   return /(?:^|\s)(?:[a-z0-9-]+:)*size-(?!fit(?:\s|$))\S+/.test(node.srcClass || "");
 }
 
+// An authored, definite length unit (px/rem/em/…) — the same predicate the capture-side probe uses to
+// call a dimension "load-bearing". Rejects auto/%/keywords and viewport/container units (those are
+// fluid laws the width/height passes already recover); a bare number (`0`) is not definite. Used to
+// read the arbitrary-value inner of a `h-[…]` / `w-[…]` source utility.
+function isDefiniteAuthoredLength(inner: string): boolean {
+  const v = inner.trim().toLowerCase();
+  if (!v) return false;
+  if (/^(auto|min-content|max-content|fit-content|inherit|initial|unset|revert)$/.test(v)) return false;
+  if (/%|vw|vh|vmin|vmax|svw|lvw|dvw|svh|lvh|dvh|\bfr\b/.test(v)) return false;
+  return /(?:^|[\s(*/+-])[\d.]+(?:px|rem|em|cm|mm|in|pt|pc|ex|ch|q)\b/.test(v);
+}
+
+/** Does the SOURCE class author an explicit, definite fixed height on this axis — `h-[<len>]`,
+ *  `min-h-[<len>]`, or the token forms (`h-<n>`, `h-px`) — at one or more breakpoints, corroborated by
+ *  geometry? This is the emission-side twin of the capture probe's authored-height guard: a banded
+ *  authored fixed height (`h-[4rem] sm:h-[4.5rem] md:h-[6.25rem]`) can still probe hFill/hAuto when the
+ *  box is a grid/flex item whose fill child (or stretched track) reproduces the box height — the
+ *  fill↔content cycle — so the probe alone would drop the baked band to `h-full`/auto. When the source
+ *  authors a definite height AND every painted viewport has a definite computed height matching its
+ *  bbox (the authored value actually resolved to that px), trust the baked per-band px. Geometry
+ *  corroboration keeps this from firing on a fluid/percentage box that merely mentions a fixed h-token
+ *  under an inactive variant. */
+function sourceFixedHeightIntent(node: IRNode, viewports: number[]): boolean {
+  if (REPLACED.has(node.tag) || node.tag === "canvas" || node.tag.includes("-")) return false;
+  if (!authorsFixedAxis(node.srcClass, "h")) return false;
+  return fixedAxisGeometryHolds(node, "h", viewports);
+}
+
+/** The WIDTH twin of sourceFixedHeightIntent: the source authors a definite `w-[<len>]`/`min-w-[<len>]`
+ *  (or token) width, corroborated by a definite computed width == bbox at every painted viewport. A
+ *  banded authored fixed width on a shrink-0 item (a testimonial avatar `h-[2.5rem] w-[2.5rem] shrink-0`
+ *  whose img child fills it) probes wAuto/wFill and would otherwise be dropped, collapsing the box to
+ *  its child's intrinsic size. Trust the authored fixed width. */
+function sourceFixedWidthIntent(node: IRNode, viewports: number[]): boolean {
+  if (REPLACED.has(node.tag) || node.tag === "canvas" || node.tag.includes("-")) return false;
+  if (!authorsFixedAxis(node.srcClass, "w")) return false;
+  return fixedAxisGeometryHolds(node, "w", viewports);
+}
+
+// True when the source class authors a definite fixed length on the given axis at any breakpoint:
+// `h-[4rem]` / `min-w-[24px]` (arbitrary), `h-px`, or a numeric token `w-24` (Tailwind's spacing scale
+// is a fixed rem length). `full`/`auto`/`screen`/fraction/`min`/`max`/`fit`/`svh`… tokens are fluid and
+// excluded. Variant-prefixed forms count (banded authored heights), matching the source-intent parser.
+function authorsFixedAxis(srcClass: string | undefined, axis: "h" | "w"): boolean {
+  if (!srcClass) return false;
+  for (const raw of srcClass.split(/\s+/).filter(Boolean)) {
+    const colon = lastTopLevelColon(raw);
+    const core = colon >= 0 ? raw.slice(colon + 1) : raw;
+    const m = new RegExp(`^(?:min-)?${axis}-(.+)$`).exec(core);
+    if (!m) continue;
+    const val = m[1]!;
+    if (val.startsWith("[") && val.endsWith("]")) {
+      if (isDefiniteAuthoredLength(val.slice(1, -1))) return true;
+      continue;
+    }
+    if (val === "px") return true;                 // 1px
+    if (/^\d+(?:\.\d+)?$/.test(val)) return true;   // spacing-scale token (fixed rem)
+  }
+  return false;
+}
+
+// Index of the variant/core separating colon at bracket depth 0 (so `h-[calc(1px:2)]` is not split on
+// an interior colon), mirroring parseSourceClass in the tailwind emitter.
+function lastTopLevelColon(raw: string): number {
+  let depth = 0, last = -1;
+  for (let i = 0; i < raw.length; i++) {
+    const ch = raw[i]!;
+    if (ch === "[" || ch === "(") depth++;
+    else if (ch === "]" || ch === ")") depth = Math.max(0, depth - 1);
+    else if (ch === ":" && depth === 0) last = i;
+  }
+  return last;
+}
+
+// Geometry corroboration for an authored fixed height/width: at EVERY painted viewport the node has a
+// definite (px, non-auto) computed value on the axis that equals its measured bbox extent. This proves
+// the authored fixed length actually resolved to the captured box (so the baked per-band px is the
+// authored value), not a fluid/percentage box that merely carries a fixed token under an inactive
+// variant. Requires ≥1 painted sample.
+function fixedAxisGeometryHolds(node: IRNode, axis: "h" | "w", viewports: number[]): boolean {
+  let painted = 0;
+  for (const vp of viewports) {
+    const cs = node.computedByVp[vp]; const nb = node.bboxByVp[vp];
+    if (!cs || !nb || !node.visibleByVp[vp] || (cs.display || "") === "none") continue;
+    const val = axis === "h" ? cs.height : cs.width;
+    const ext = axis === "h" ? nb.height : nb.width;
+    if (!val || val === "auto" || !/px$/.test(val)) return false;
+    if (!(ext > 0)) return false;
+    if (Math.abs(pf(val) - ext) > Math.max(1.5, 0.01 * ext)) return false;
+    painted++;
+  }
+  return painted >= 1;
+}
+
 const ABSOLUTE_MEDIA_FILL_TAGS = new Set(["img", "picture", "video"]);
 
 /** An absolutely-positioned media layer authored as a full-cover background: `position:absolute;
@@ -1397,7 +1639,7 @@ function fillsToCapWidth(node: IRNode, parentNode: IRNode | undefined, viewports
  *  margins (those make the width load-bearing). */
 function fluidPercentByVp(node: IRNode, parentNode: IRNode | undefined, viewports: number[]): Record<number, string> | null {
   if (!parentNode || REPLACED.has(node.tag) || node.tag.includes("-")) return null;
-  type S = { vp: number; ratio: number; container: number; w: number; flexRow: boolean };
+  type S = { vp: number; ratio: number; container: number; w: number; flexRow: boolean; wMin?: number; wMax?: number };
   const samples: S[] = [];
   for (const vp of viewports) {
     const cs = node.computedByVp[vp]; const pcs = parentNode.computedByVp[vp];
@@ -1413,12 +1655,25 @@ function fluidPercentByVp(node: IRNode, parentNode: IRNode | undefined, viewport
     const flexGridItem = /(?:^|-)(?:flex|grid)$/.test(pdisp);
     const blockLevel = /^(block|flow-root|list-item|flex|grid|inline-block)$/.test(cs.display || "");
     if (!flexGridItem && !blockLevel) return null;
+    // A GRID item's `%` width resolves against its GRID AREA (its track span), NOT the grid
+    // container's content box. When the grid has more than one column track, the parent-content-box
+    // ratio computed below is against the wrong containing block — the browser would apply that % to
+    // the ~1-column track, collapsing the item (24.5% of 1240px emitted where % hits a 302px track →
+    // 74px column). We have no direct track-width evidence, so bail for a multi-column grid item and
+    // let it fall to its authored width (auto / source-intent). Single-column grids are safe: the one
+    // track spans the full content box, so the ratio base is correct.
+    const isGridItem = /(?:^|-)grid$/.test(pdisp);
+    if (isGridItem) {
+      const cols = parseTracks(pcs.gridTemplateColumns);
+      if (!cols || cols.length > 1) return null;
+    }
     const container = pb.width - pf(pcs.paddingLeft) - pf(pcs.paddingRight) - pf(pcs.borderLeftWidth) - pf(pcs.borderRightWidth);
     if (container <= 0) return null;
     const ratio = nb.width / container;
     if (!(ratio > 0.04 && ratio < 1.02)) return null;                   // not a clean fraction of the container
     const flexRow = /(?:^|-)flex$/.test(pdisp) && /^(row|row-reverse)$/.test(pcs.flexDirection || "row");
-    samples.push({ vp, ratio, container, w: nb.width, flexRow });
+    const sz = node.sizingByVp?.[vp];
+    samples.push({ vp, ratio, container, w: nb.width, flexRow, wMin: sz?.wMin, wMax: sz?.wMax });
   }
   if (samples.length < 2) return null;
   const ws = samples.map((s) => s.w);
@@ -1444,7 +1699,21 @@ function fluidPercentByVp(node: IRNode, parentNode: IRNode | undefined, viewport
   // Each sample is a clean fraction that reproduces its captured px. Snap to 0.5% and verify.
   const out: Record<number, string> = {};
   for (const s of samples) {
-    const pct = Math.round(s.ratio * 200) / 2;                          // nearest 0.5%
+    // Default: nearest 0.5% (no geometry churn for ordinary boxes). But a CONTENT-FIT box — one sitting
+    // at its own max-content width (a nowrap pill: captured w ≈ wMax, and genuinely wrappable so wMin <
+    // wMax) — has NO slack: rounding the % DOWN emits a width below its intrinsic content, and the clone
+    // wraps it onto a second line (task #26: a 71.70% pill → 71.5% → 245.24px < 245.94px content → wrap,
+    // +23.5px section). For such a node snap UP (ceil to the 0.5% step) only when the nearest-rounded px
+    // falls below wMax by more than 0.25px, so the emitted width never lands short of the content it must
+    // hold. All other nodes keep round-to-nearest.
+    const nearest = Math.round(s.ratio * 200) / 2;
+    let pct = nearest;
+    const wMax = s.wMax, wMin = s.wMin;
+    const contentFit = wMax != null && wMin != null && wMin < wMax - 2 &&
+      Math.abs(s.w - wMax) <= Math.max(1.5, 0.01 * wMax);
+    if (contentFit && (nearest / 100) * s.container < wMax! - 0.25) {
+      pct = Math.ceil(s.ratio * 200) / 2;                               // snap UP to clear intrinsic content width
+    }
     if (Math.abs((pct / 100) * s.container - s.w) > Math.max(1.5, 0.01 * s.w)) return null;
     out[s.vp] = `${pct}%`;
   }
@@ -1519,6 +1788,18 @@ function contentSizedFlexRow(container: IRNode, viewports: number[]): Set<string
   for (const vp of viewports) for (const it of items) {
     const cs = it.computedByVp[vp]; if (cs && pf(cs.flexGrow) > 0) return null;
   }
+  // The sizing probe is ground truth: if it proved `width:auto` does NOT reproduce an item's width at
+  // any painted viewport (`wAuto:false`), that item is load-bearing and cannot be dropped. Because this
+  // rule is all-or-nothing per line (dropping a subset shifts siblings via justify-content), one such
+  // item vetoes the whole line. This catches a wrapping-text item — e.g. a paragraph in a
+  // `justify-content:flex-end` row paints at its balanced-wrap width (below max-content), but
+  // `width:auto` on the block child fills the line to max-content — which the geometric slack test
+  // alone (no shrink fired) would wrongly convert to auto.
+  for (const it of items) {
+    for (const vp of viewports) {
+      if (it.sizingByVp?.[vp]?.wAuto === false) return null;
+    }
+  }
   // At every width: the visible items + gaps + margins must not overflow the container (slack ≥ 0).
   for (const vp of viewports) {
     const pcs = container.computedByVp[vp]; const pb = container.bboxByVp[vp];
@@ -1902,6 +2183,12 @@ function contentSizedFlexItemAuto(node: IRNode, parentNode: IRNode | undefined,
     const cs = node.computedByVp[vp]; const pcs = parentNode.computedByVp[vp];
     const nb = node.bboxByVp[vp]; const pb = parentNode.bboxByVp[vp];
     if (!cs || !pcs || !nb || !pb || !node.visibleByVp[vp] || (cs.display || "") === "none") continue;
+    // The sizing probe is ground truth: if it proved `width:auto` does NOT reproduce the captured
+    // width at any painted viewport (`wAuto:false`), the geometric "never shrank ⇒ at content size"
+    // read below is wrong — e.g. a wrapping paragraph in a `justify-content:flex-end` row paints at
+    // its balanced-wrap width (below max-content), but `width:auto` on the block child fills the line
+    // to max-content and left-aligns it. Honor the probe over the heuristic.
+    if (node.sizingByVp?.[vp]?.wAuto === false) return false;
     if (!/^(flex|inline-flex)$/.test(pcs.display || "")) return false;
     const dir = pcs.flexDirection || "row";
     if (dir !== "row" && dir !== "row-reverse") return false;        // width = main axis only for rows
@@ -1960,6 +2247,31 @@ function flexRowHasSlack(container: IRNode, viewports: number[]): boolean {
   return checked >= 1;
 }
 
+/** Does an in-flow element CHILD derive its HEIGHT from its parent's box (fill it) at this viewport?
+ *  Two ways:
+ *   • the sizing probe measured `height:100%` reproduces and `height:auto` does NOT (hFill && !hAuto);
+ *   • the child is an UN-PROBED replaced element that soaks up the parent box height — a `<picture>`
+ *     (the probe skips it — walker's probe excludes replaced tags) or an object-fit:cover img/video —
+ *     whose border-box height ≈ the parent's CONTENT-box height. Such a child's extent equals the
+ *     parent's height only BECAUSE it fills it (object-fit:cover paints to any box, `<picture>` sizes
+ *     its inner img to the box), so it is NOT content evidence and must not explain away the parent's
+ *     authored height. Without this a `<picture h-full>` reads as real content, the authored parent
+ *     height is dropped, and the inner img re-derives from its selected source's natural aspect.
+ *  `parentContentH` is the parent's content-box height (border-box minus padding/border, top+bottom). */
+function childDerivesHeightFromParent(child: IRNode, vp: number, parentContentH: number): boolean {
+  const csz = child.sizingByVp?.[vp];
+  if (csz && csz.hFill === true && csz.hAuto === false) return true;
+  const ccs = child.computedByVp[vp]; const cb = child.bboxByVp[vp];
+  if (!ccs || !cb) return false;
+  const isPicture = child.tag === "picture";
+  const isCoverReplaced = REPLACED.has(child.tag) && /cover/.test(ccs.objectFit || "");
+  if (!isPicture && !isCoverReplaced) return false;
+  if (!(parentContentH > 0)) return false;
+  // Border-box height fills the parent content box (≤2px slop). An intrinsically-shorter media that
+  // merely SITS in a taller box (natural-aspect logo) fails this and is treated as real content.
+  return Math.abs(cb.height - parentContentH) <= Math.max(2, 0.01 * parentContentH);
+}
+
 /** Whether a node's height can FLOW (drop the baked px) — true when, at every sampled width, its
  *  border-box height is either content-driven (== the extent of its in-flow children + padding) or
  *  cross-axis STRETCH (a flex-row / grid item filling its container's content height). Both
@@ -1977,6 +2289,24 @@ function heightFlows(node: IRNode, parentNode: IRNode | undefined, viewports: nu
     if (pos !== "static" && pos !== "relative") return false;
     if ((cs.overflowY || cs.overflow || "visible") !== "visible") return false;
     if ((cs.display || "") === "none") continue;
+    // The sizing probe proved this height AUTHORED-EXPLICIT: height:auto did NOT reproduce the box
+    // (hAuto:false) and the box is not a fill child of its own parent (hFill:false). The measured
+    // px is then load-bearing — dropping it collapses the box. This overrides the structural flow
+    // reasoning below, which can read the height as content-driven via a CIRCULAR pair (two nested
+    // authored-height boxes each "explaining" the other's extent) and drop both. Bail so the
+    // authored height survives. (heightProbeDrops, OR'd with this at the call site, also refuses to
+    // drop an hAuto:false box — so the two signals agree and the authored px is kept.)
+    const sz = node.sizingByVp?.[vp];
+    if (sz && sz.hAuto === false && sz.hFill === false) return false;
+    // A flex COLUMN that DISTRIBUTES free space (justify-content space-between/around/evenly, or the
+    // packed alignments that pin the last child away from the top): the box height is LOAD-BEARING —
+    // it sets the free space the children spread through. The content-extent check below would read
+    // the last child reaching the box bottom as "content-sized", but that extent only equals the box
+    // bottom BECAUSE the distribution pushed it there. Dropping the height collapses the gaps.
+    if (/flex/.test(cs.display || "") && /column/.test(cs.flexDirection || "row") &&
+        /^(space-between|space-around|space-evenly|center|flex-end|end)$/.test(cs.justifyContent || "")) {
+      return false;
+    }
     // A flex COLUMN whose in-flow child fills it via flex-grow: the box's height is LOAD-BEARING,
     // not content-derived. The content-extent check below would read the box as content-sized — but
     // that extent IS the grown child, which only reaches the box bottom BECAUSE the box has this
@@ -1998,6 +2328,7 @@ function heightFlows(node: IRNode, parentNode: IRNode | undefined, viewports: nu
     // header). Dropping the height then lets the fill child re-derive from its aspect ratio and inflate
     // (a 240px hero → 720px @16/9). Do NOT flow such a box's height.
     let allInflowFill = true;
+    const nodeContentH = nb.height - pf(cs.paddingTop) - pf(cs.paddingBottom) - pf(cs.borderTopWidth) - pf(cs.borderBottomWidth);
     for (const c of node.children) {
       if (isTextChild(c)) continue;
       const ccs = c.computedByVp[vp]; const cb = c.bboxByVp[vp];
@@ -2005,8 +2336,7 @@ function heightFlows(node: IRNode, parentNode: IRNode | undefined, viewports: nu
       if (ccs.position === "absolute" || ccs.position === "fixed") continue;
       if ((ccs.float || "none") !== "none") continue;
       hasChild = true;
-      const csz = c.sizingByVp?.[vp];
-      if (!(csz && csz.hFill === true && csz.hAuto === false)) allInflowFill = false;
+      if (!childDerivesHeightFromParent(c, vp, nodeContentH)) allInflowFill = false;
       bottom = Math.max(bottom, cb.y + cb.height);
       bottomMargin = Math.max(bottomMargin, cb.y + cb.height + Math.max(0, pf(ccs.marginBottom)));
     }
@@ -2123,10 +2453,11 @@ function absoluteHeightFill(node: IRNode, parentNode: IRNode | undefined, viewpo
  *  aren't probed (the probe skips them), so this never fires on img/svg. */
 function heightProbeFills(node: IRNode, viewports: number[]): boolean {
   if (process.env.NO_HFILL) return false; // diagnostic toggle
-  let painted = 0;
+  let painted = 0; let paintedTotal = 0;
   for (const vp of viewports) {
     const cs = node.computedByVp[vp];
     if (!cs || !node.visibleByVp[vp] || (cs.display || "") === "none") continue;
+    paintedTotal++;
     const pos = cs.position || "static";
     if (pos !== "static" && pos !== "relative") return false;
     const s = node.sizingByVp?.[vp];
@@ -2134,7 +2465,11 @@ function heightProbeFills(node: IRNode, viewports: number[]): boolean {
     if (!s.hFill || s.hAuto) return false;         // must fill at 100% AND not be content-sized
     painted++;
   }
-  return painted >= 2;
+  // Normally require ≥2 painted viewports so the fill verdict is corroborated across widths. But a
+  // responsive-only variant (a `max-md:`-scoped node) is PAINTED at only one captured viewport — its
+  // single unanimous probe reading is the COMPLETE evidence set, not a lone sample, so accept it.
+  // The parent still confers a definite height (its own band-baked height), so 100% resolves safely.
+  return painted >= 2 || (painted === 1 && paintedTotal === 1);
 }
 
 /** Does this node confer a DEFINITE height to its children (so their height:100% resolves)? True when:
@@ -2179,11 +2514,22 @@ function confersDefiniteHeight(node: IRNode, parentNode: IRNode | undefined, got
  *  change. transform-origin follows transform (skipped when no transform varies). */
 const ANIM_OWNED = new Set(["opacity", "transform"]);
 const EMPTY_SET = new Set<string>();
-function animOwnedProps(node: IRNode, baseVp: number): Set<string> {
-  const cs = node.computedByVp[baseVp];
-  if (!cs || (cs.animationName || "none") === "none") return EMPTY_SET;
-  if (!/infinite/.test(cs.animationIterationCount || "1")) return EMPTY_SET;
-  return ANIM_OWNED;
+/** True when an INFINITE CSS animation is active on the node at this viewport (so it perpetually
+ *  drives opacity/transform — the captured value is a frozen animation phase, not design). */
+function hasInfiniteAnim(cs: StyleMap | undefined): boolean {
+  if (!cs || (cs.animationName || "none") === "none") return false;
+  return /infinite/.test(cs.animationIterationCount || "1");
+}
+/** Properties an infinite animation owns (so their per-viewport captured values are frozen phase
+ *  noise to suppress). Sampled across ALL emitted viewports, not just the base: a CSS marquee that
+ *  runs only below a breakpoint (Webflow's `max-lg` logo/text tracks) is `animation:none` at the
+ *  base (desktop) width but still freezes a random `translateX` at the mobile/tablet bands — banding
+ *  those bakes a mid-scroll offset that shifts content offscreen at rest. When the animation owns the
+ *  transform at ANY width, the frozen per-band deltas are dropped everywhere and the base value holds
+ *  (the runtime `@keyframes` starts at translateX(0), so the strip renders aligned until it animates). */
+function animOwnedProps(node: IRNode, viewports: number[]): Set<string> {
+  for (const vp of viewports) if (hasInfiniteAnim(node.computedByVp[vp])) return ANIM_OWNED;
+  return EMPTY_SET;
 }
 
 
@@ -2205,6 +2551,9 @@ function declsForViewport(
   geometry: GeometryPlan = GEOMETRY_NONE,
   dropGridRows = false,
   dropViewportMaxWidth = false,
+  nowrapText = false,
+  keepIdentityTransform = false,
+  forceHeight = false,
 ): Map<string, string> {
   const cs = node.computedByVp[vp];
   const out = new Map<string, string>();
@@ -2292,8 +2641,32 @@ function declsForViewport(
   // absolutely-positioned children). Without emitting it the block collapses to
   // its content in the clone. Content-filled blocks stay auto so margin
   // collapsing is preserved.
-  let explicitHeight = false;
+  // `forceHeight`: the caller proved this node authors a geometry-corroborated fixed height
+  // (sourceFixedHeightIntent) but the box's own content extent can't re-derive it (a shrink-0 box whose
+  // child fills it — the avatar case), so none of the structural explicit-height tests below fire. Trust
+  // the authored value and emit the baked per-band px.
+  let explicitHeight = forceHeight;
   const nb = node.bboxByVp[vp];
+  // Probe ground truth, emission twin of the heightFlows keep (see the hAuto/hFill guard there):
+  // the sizing probe proved height:auto did NOT reproduce this box (hAuto:false) AND it is not a
+  // fill child of its own parent (hFill:false), so the captured px is AUTHORED and load-bearing.
+  // heightFlows refuses to FLOW such a box, but the emission gate below still needs a matching keep
+  // or the height is dropped when the fill-child evidence (the "taller than content" / all-inflow-fill
+  // tests) can't fire — an inline `<a>` child probes hAuto:true and content extent equals the box, so
+  // neither structural test detects the authored height. Trust the node's own probe.
+  {
+    const osz = node.sizingByVp?.[vp];
+    // Never trust this probe on a document-height wrapper. A root landmark (body/html/main) — or
+    // any node whose captured box IS the page's scroll height — probes hAuto:false/hFill:false as
+    // measurement noise (min-h-screen + the %-height re-measure chain at document level), not an
+    // authored height. Baking that px pins the whole page to a fixed height: combined with an
+    // `overflow:hidden` main it hard-clips any content-height drift, and it makes the layout gate's
+    // heightDelta tautologically zero (gate blindness). Such wrappers must keep flowing.
+    const isRootWrapper = tag === "body" || tag === "html" || tag === "main";
+    const isPageHeightBox = !!rootScrollHeight && !!nb && nb.height > 0 &&
+      Math.abs(nb.height - rootScrollHeight) <= rootScrollHeight * 0.02;
+    if (!noCollapse && !isLeaf && !isRootWrapper && !isPageHeightBox && cs.height && cs.height !== "auto" && osz && osz.hAuto === false && osz.hFill === false) explicitHeight = true;
+  }
   if (!noCollapse && !isLeaf && cs.height && cs.height !== "auto" && nb) {
     const top = nb.y + (parseFloat(cs.paddingTop || "0") || 0) + (parseFloat(cs.borderTopWidth || "0") || 0);
     let contentBottom = top;       // includes trailing margins (for taller detection)
@@ -2304,6 +2677,7 @@ function declsForViewport(
     // height only BECAUSE they fill it — it is not content-derived evidence, so it must
     // not be allowed to "explain away" an authored height below.
     let allInflowFill = true;
+    const nodeContentH = nb.height - (parseFloat(cs.paddingTop || "0") || 0) - (parseFloat(cs.paddingBottom || "0") || 0) - (parseFloat(cs.borderTopWidth || "0") || 0) - (parseFloat(cs.borderBottomWidth || "0") || 0);
     for (const c of node.children) {
       if (isTextChild(c)) continue;
       const ccs = c.computedByVp[vp]; const cb = c.bboxByVp[vp];
@@ -2314,10 +2688,10 @@ function declsForViewport(
       if (ccs.position === "absolute" || ccs.position === "fixed") continue;
       if ((ccs.float || "none") !== "none") continue;
       inflowCount++;
-      const csz = c.sizingByVp?.[vp];
-      // A fill child: the probe measured height:100% reproduces AND auto does not (hFill && !hAuto).
-      // No probe data (older captures) ⇒ treat as real content (conservative: leave allInflowFill off).
-      if (!(csz && csz.hFill === true && csz.hAuto === false)) allInflowFill = false;
+      // A fill child derives its height from this box: probe hFill && !hAuto, OR an un-probed
+      // <picture>/object-fit:cover replaced child whose border-box == this box's content height.
+      // No probe data on a plain block child ⇒ treat as real content (leave allInflowFill off).
+      if (!childDerivesHeightFromParent(c, vp, nodeContentH)) allInflowFill = false;
       contentBottom = Math.max(contentBottom, cb.y + cb.height + (parseFloat(ccs.marginBottom || "0") || 0));
       borderBottom = Math.max(borderBottom, cb.y + cb.height);
     }
@@ -2353,14 +2727,20 @@ function declsForViewport(
   // intro — body/html { height:100vh; overflow-y:scroll|hidden } — can be captured in
   // that transient state, pinning the root to one viewport so it CLIPS its overflowing
   // content; the clone's document.scrollHeight then collapses to one viewport and the
-  // page renders truncated (paco.me). The lock is provably transient when the source's
-  // OWN captured scrollHeight exceeds the pinned height (the real document scrolled
-  // taller) — unlike a genuine internal-scroll shell, whose scrollHeight matches. Drop
-  // the clamp (height + clipping overflow-y) so the root grows to its content.
+  // page renders truncated (paco.me). Two independent signals prove the lock is transient:
+  //   • captured scrollHeight exceeds the pinned height (the real document scrolled taller); OR
+  //   • the IR's own IN-FLOW content extent (max descendant border-box bottom) exceeds the clamp.
+  // The SECOND signal is essential for an email-capture popup that scroll-LOCKS the page: the
+  // lock collapses `document.scrollHeight` down to the viewport (== clamp), so the scrollHeight
+  // test can never fire in exactly the worst case — but the in-flow sections still carry their
+  // real coordinates, so the content extent (5000px+ on a real homepage) still betrays the clamp.
+  // A genuine internal-scroll shell has matching content extent AND scrollHeight, so neither fires.
   const clampH = parseFloat(cs.height || "");
+  const contentExtent = (tag === "body" || tag === "html") ? irContentExtent(node, vp) : 0;
   const rootUnclamp =
     (tag === "body" || tag === "html") &&
-    !!rootScrollHeight && clampH > 0 && rootScrollHeight > clampH + 4 &&
+    clampH > 0 &&
+    ((!!rootScrollHeight && rootScrollHeight > clampH + 4) || contentExtent > clampH + 4) &&
     /^(scroll|hidden|auto|clip)$/.test(cs.overflowY || cs.overflow || "visible");
   // A pure-text leaf's height is fully content-derived (padding/border + lines × line-height).
   // We reproduce the font, line-height, padding and width, so its height auto-resolves to the
@@ -2393,8 +2773,13 @@ function declsForViewport(
   } else if (cs.height && cs.height !== "auto" && !isTableWithCaption && !rootUnclamp && !dropHeight && (!isInlineOnly || REPLACED.has(tag)) && (noCollapse || isLeaf || explicitHeight)) {
     out.set("height", cs.height);
   }
+  const plannedMinHeight = geometry.minHeightByVp?.[vp];
   if (cs.minHeight && cs.minHeight !== "0px" && cs.minHeight !== "auto") {
-    out.set("min-height", isViewportHeight(cs.minHeight, vp) ? "100vh" : cs.minHeight);
+    if (plannedMinHeight) {
+      out.set("min-height", plannedMinHeight);
+    } else {
+      out.set("min-height", isViewportHeight(cs.minHeight, vp) ? "100vh" : cs.minHeight);
+    }
   }
 
   // borders (complete triple per side, only when width > 0). When all four sides are
@@ -2452,6 +2837,14 @@ function declsForViewport(
     // emitted once below so it never bands per-viewport-px.
     if (prop === "gridTemplateColumns" && gridCols !== undefined) continue;
     // grid-template-rows likewise replaced by the fluid (1fr) template when one was inferred.
+    // NEVER drop a `subgrid` template: it is a STRUCTURAL keyword (the row tracks are inherited from
+    // the parent grid so both stacked layers share row sizing), not a frozen per-viewport px regime.
+    // `dropGridRows` exists to strip baked px row heights in reflow mode, but computed
+    // getComputedStyle reports the keyword literally ("subgrid [] …") — dropping it collapses the
+    // empty layer's row-1 to 0 and its media overlaps the text layer. Emit it (tailwind maps it to
+    // `grid-rows-subgrid`); the fluidGridRows path already refuses to touch subgrid nodes, so gridRows
+    // is undefined here and this keyword flows straight through.
+    if (prop === "gridTemplateRows" && /\bsubgrid\b/.test(value || "")) { out.set("grid-template-rows", "subgrid"); continue; }
     if (prop === "gridTemplateRows" && (gridRows !== undefined || dropGridRows)) continue;
     // fill-to-cap sets max-width to the recovered cap (above); don't let the source value re-emit it.
     if (prop === "maxWidth" && widthPlan.kind === "fillcap") continue;
@@ -2475,6 +2868,13 @@ function declsForViewport(
       // list reset is none; emit whatever the source uses (incl. none).
     } else if (prop === "minWidth") {
       if (value === "auto" || (value === "0px" && !isFlexGridItem) || (value === "0px" && inScrollXFlexStrip)) continue;
+    } else if (prop === "transform") {
+      // Emit the identity `transform:none` explicitly at a viewport whose value is `none` WHEN the node
+      // carries a non-identity transform at some OTHER band — otherwise the non-identity value cascades
+      // across bands and freezes at a width the source left untransformed. (Identity matrices are already
+      // canonicalized to the literal "none" upstream, so the string compare is reliable.) When the node
+      // is identity everywhere, this stays a normal default elision.
+      if (value === "none" && !keepIdentityTransform) continue;
     } else if (def === "__never__") {
       // always emit (display/color/fontFamily/fontSize handled below for inherit)
     } else if (isDefault(def, value)) {
@@ -2503,17 +2903,41 @@ function declsForViewport(
     out.set(kebab(prop), outValue);
   }
 
+  // Wrap-vulnerable single-line text: the text renders on one line at every captured width and its
+  // unwrapped width nearly equals the container's available width, so a sub-pixel width shortfall in
+  // the clone (a column resolving ~0.6px narrower) tips it onto a second line, shifting everything
+  // below. `white-space:nowrap` holds it to one line — identical to the capture (already single-line
+  // at every width) but immune to the rounding shortfall. Only the source `whiteSpace` value that
+  // already collapses runs (`normal`/`nowrap`) is overridden; `pre`/`pre-wrap`/`break-spaces` preserve
+  // authored whitespace and are left untouched (the caller's detector also excludes them).
+  if (nowrapText) out.set("white-space", "nowrap");
+
   // Centered max-width container: emit auto side margins so the browser centers
   // it at every width. getComputedStyle sometimes reports 0 for resolved auto
   // margins at wide viewports, so replaying px would left-align the clone.
+  // The fill-inset guard lives in the centering DECISION (centeredAtVp): a full-width block merely
+  // inset by a fixed gutter is no longer flagged centred, so its literal px margins are kept and it
+  // never bleeds full-bleed from a `margin:auto` that resolves to 0.
   if (isCentered) {
     out.set("margin-left", "auto");
     out.set("margin-right", "auto");
   }
 
   // Root un-clamp: relax the clipping vertical overflow so the document scrolls at the
-  // window level (no spurious scrollbar gutter) and grows to its content height.
-  if (rootUnclamp) out.set("overflow-y", "visible");
+  // window level (no spurious scrollbar gutter) and grows to its content height. Popup
+  // vendors also inject `position:absolute|fixed` + `overflow:hidden` on <body> to freeze
+  // the page under their modal; that lock state gets captured as the body's computed style
+  // and, unstripped, hard-clips the clone to one screen (it can't scroll). Strip both — the
+  // real body is `position:static; overflow:visible` — so the un-clamped root scrolls normally.
+  if (rootUnclamp) {
+    out.set("overflow-y", "visible");
+    out.set("overflow-x", "visible");
+    out.delete("overflow");
+    out.delete("height");
+    const posV = out.get("position");
+    if (posV === "absolute" || posV === "fixed") out.delete("position");
+    for (const side of ["top", "right", "bottom", "left"]) out.delete(side);
+  }
 
   // Fluid grid columns (fr) replace the baked per-viewport px tracks so the grid scales.
   if (gridCols !== undefined) out.set("grid-template-columns", gridCols);
@@ -2605,6 +3029,31 @@ function marginsVaryAcrossVps(node: IRNode): boolean {
   return ms.length >= 2 && Math.max(...ms) - Math.min(...ms) > 1;
 }
 
+/** Does the box's WIDTH grow in near-lockstep with its container across viewports? Then it is a
+ *  full-width block INSET by a fixed gutter (an `mx-4 md:mx-8` section — box == container − 2·gutter),
+ *  NOT a centred content box (whose width stays roughly constant while the container grows and the
+ *  side margins absorb the widening slack). The two are indistinguishable at a SINGLE width (both show
+ *  equal side gaps), and the sizing probe reads BOTH as `wAuto:true` (auto reproduces the inset width).
+ *  The discriminator is the trajectory: a centred 600px box in a 375→1280 container barely widens
+ *  (Δbox ≪ Δcontainer), while a gutter-inset section tracks the container (Δbox ≈ Δcontainer). Used to
+ *  keep auto-margin centring OFF a width-dropped fill-inset block — where `margin:auto` resolves to 0
+ *  and blows it full-bleed — while still centring genuinely content-constrained blocks. */
+function widthTracksContainerFill(node: IRNode, parentNode: IRNode, viewports: number[]): boolean {
+  const bw: number[] = []; const cw: number[] = [];
+  for (const vp of viewports) {
+    const nb = node.bboxByVp[vp]; const pb = parentNode.bboxByVp[vp]; const pcs = parentNode.computedByVp[vp];
+    if (!nb || !pb || !node.visibleByVp[vp]) continue;
+    const content = pb.width - pf(pcs?.paddingLeft) - pf(pcs?.paddingRight) - pf(pcs?.borderLeftWidth) - pf(pcs?.borderRightWidth);
+    if (!(content > 0)) continue;
+    bw.push(nb.width); cw.push(content);
+  }
+  if (bw.length < 2) return false;
+  const dBox = Math.max(...bw) - Math.min(...bw);
+  const dCon = Math.max(...cw) - Math.min(...cw);
+  if (dCon <= 8) return false;                 // container barely varies → trajectory says nothing
+  return dBox / dCon > 0.5;                     // box widens ≥ half as fast as the container → tracks it
+}
+
 function centeredAtVp(node: IRNode, parentNode: IRNode, vp: number): boolean {
   const cs = node.computedByVp[vp];
   const nb = node.bboxByVp[vp];
@@ -2638,7 +3087,22 @@ function centeredAtVp(node: IRNode, parentNode: IRNode, vp: number): boolean {
   // marquee). Converting fixed spacing to `auto` deletes it when the parent shrink-wraps the child
   // (auto resolves to 0) — exactly how the testimonial inter-card gap vanished. Literal margins
   // reproduce that spacing at every width regardless of the parent's resolved width.
-  if (ml > 0.5 && Math.abs(ml - mr) < 1 && nb.width < pb.width - 4 && marginsVaryAcrossVps(node)) return true;
+  // The width must ALSO be genuinely constrained: a box the sizing probe reads as a container-FILL
+  // (`width:100%` reproduces it) has no free space for auto margins to absorb — the emitted width
+  // is set to 100% (fill/fillcap), so `margin:auto` resolves to 0 and silently deletes real literal
+  // px side margins, blowing a padded pill/section out to full-bleed. Equal literal margins are the
+  // geometric TWIN of centering slack (both split the free space symmetrically), so this probe read
+  // is the only reliable discriminator between them; when the box fills, keep the literal margins.
+  // A box the probe reads as a container-FILL (`width:100%` reproduces it) has no free space for auto
+  // margins to absorb. So does a full-width block merely INSET by a fixed gutter (`mx-4 md:mx-8`): the
+  // probe reads it `wAuto:true, wFill:false` (auto reproduces the inset width) and its symmetric
+  // margins vary per breakpoint — so it slips past `!fillsAtVp` and looks centred at any single width,
+  // yet its width TRACKS the container. Emitting `margin:auto` on it (after its width is dropped to
+  // auto) resolves the margins to 0 and blows it full-bleed. `widthTracksContainerFill` catches that
+  // trajectory; a genuinely centred content box (constant width, ballooning margins) does not track.
+  const fillsAtVp = node.sizingByVp?.[vp]?.wFill === true;
+  const gutterInset = widthTracksContainerFill(node, parentNode, Object.keys(node.computedByVp).map(Number));
+  if (ml > 0.5 && Math.abs(ml - mr) < 1 && nb.width < pb.width - 4 && marginsVaryAcrossVps(node) && !fillsAtVp && !gutterInset) return true;
   if (parentFlexGrid) return false;
   // Signal 2: bbox-centered within the parent content box with ~0 reported margins.
   if (Math.abs(ml) > 0.5 || Math.abs(mr) > 0.5) return false; // margins already explain position
@@ -2651,6 +3115,45 @@ function centeredAtVp(node: IRNode, parentNode: IRNode, vp: number): boolean {
   return leftGap > 1 && rightGap > 1 && Math.abs(leftGap - rightGap) < 1.5 && nb.width < contentRight - contentLeft - 2;
 }
 
+/** A single-line text leaf whose unwrapped width nearly fills its container's available width at
+ *  EVERY captured viewport where it's painted — so any sub-pixel width shortfall in the clone (a
+ *  column resolving fractionally narrower) tips it onto a second line. Such a node earns an explicit
+ *  `white-space:nowrap` (see declsForViewport) to stay one line as it did in the capture.
+ *  Conservative by construction — every guard must hold at every painted viewport:
+ *   • text leaf (direct text, no element children), whitespace not already preserved (`pre*`);
+ *   • single line: box height ≈ one line box (line-height + vertical padding/border), so a genuinely
+ *     wrapping paragraph (≥2 line boxes tall) is excluded;
+ *   • wrap-vulnerable: max-content (unwrapped) width ≥ available container width − 2 and ≤ it + 1 —
+ *     the text needs essentially all the available width, with no slack for a rounding shortfall;
+ *   • genuinely wrappable: min-content < max-content − 2, so a single unbreakable token (which can
+ *     never wrap, making nowrap a redundant no-op) is skipped to keep the emission minimal.
+ *  Relies on the sizing probe's wMin/wMax (present only for in-flow probed leaves); absent ⇒ no emit. */
+function nowrapWrapVulnerable(node: IRNode, parentNode: IRNode | undefined, viewports: number[]): boolean {
+  if (!parentNode) return false;
+  if (hasElementChild(node)) return false;
+  if (!node.children.some((c) => isTextChild(c) && c.text.trim() !== "")) return false;
+  if (REPLACED.has(node.tag) || node.tag === "canvas" || node.tag.includes("-")) return false;
+  let painted = 0;
+  for (const vp of viewports) {
+    const cs = node.computedByVp[vp]; const nb = node.bboxByVp[vp];
+    if (!cs || !nb || !node.visibleByVp[vp] || (cs.display || "") === "none") continue;
+    if (!(nb.width > 0) || !(nb.height > 0)) continue;
+    const ws = cs.whiteSpace || "normal";
+    if (ws !== "normal" && ws !== "nowrap") return false; // pre/pre-wrap/break-spaces preserve authored whitespace
+    const sz = node.sizingByVp?.[vp];
+    const wMax = sz?.wMax; const wMin = sz?.wMin;
+    if (wMax == null || wMin == null) return false;
+    const lineBox = pf(cs.lineHeight) + pf(cs.paddingTop) + pf(cs.paddingBottom) + pf(cs.borderTopWidth) + pf(cs.borderBottomWidth);
+    if (!(lineBox > 0) || Math.abs(nb.height - lineBox) > 2.5) return false; // not single-line
+    const avail = containingWidthAt(node, parentNode, vp);
+    if (avail == null) return false;
+    if (!(wMax >= avail - 2 && wMax <= avail + 1)) return false; // not right at the container edge
+    if (!(wMin < wMax - 2)) return false;                        // single unbreakable token — can't wrap
+    painted++;
+  }
+  return painted >= 1;
+}
+
 function hasPxMaxWidthCap(node: IRNode, viewports: number[]): boolean {
   const caps: number[] = [];
   for (const vp of viewports) {
@@ -2667,6 +3170,59 @@ function hasPxMaxWidthCap(node: IRNode, viewports: number[]): boolean {
   return max > 0 && max - min <= Math.max(2, max * 0.02);
 }
 
+/** A centred max-width container that also qualifies when it is a FLEX/GRID ITEM (which
+ *  `planWidth` case (a) and `centeredAtVp` both bail on — a flex/grid item is normally positioned by
+ *  the parent layout). The pattern: `width:100%; max-width:W; margin:0 auto` — the box fills its
+ *  container below the cap and centres (symmetric free space) above it. `margin:auto` centres a
+ *  flex/grid item along the main axis exactly as it centres a block, so emitting `mx-auto` is correct
+ *  here too; freezing the captured side margins (which vary per width — 32/47/67/324px) instead
+ *  left-aligns the box at any non-captured width.
+ *
+ *  This is SAFE (unlike the width-dropped fill-inset case `centeredAtVp` guards against, where
+ *  `margin:auto` resolves to 0 and blows the box full-bleed) precisely because a px `max-width` cap
+ *  is RETAINED at every band: the cap holds the width, so `margin:auto` can only absorb the centring
+ *  slack, never over-widen. The `max-width` cap may VARY per viewport (a fluid
+ *  `min(Wpx, 100% − 2·gutter)` resolves to a different px per width) — we accept per-band caps and let
+ *  the normal `max-width` emission carry them, mirroring `planWidth` case (a)'s documented reasoning.
+ *
+ *  Every guard holds over the painted samples (≥2), and centring must be OBSERVED (symmetric positive
+ *  free space with equal margins) at ≥1 band where the container exceeds the cap: */
+function isCappedCenteredContainer(node: IRNode, parentNode: IRNode | undefined, viewports: number[]): boolean {
+  if (!parentNode || REPLACED.has(node.tag) || node.tag.includes("-")) return false;
+  let painted = 0;
+  let sawCenter = false;
+  for (const vp of viewports) {
+    const cs = node.computedByVp[vp]; const pcs = parentNode.computedByVp[vp];
+    const nb = node.bboxByVp[vp]; const pb = parentNode.bboxByVp[vp];
+    if (!cs || !pcs || !nb || !pb || !node.visibleByVp[vp] || (cs.display || "") === "none" || !(nb.width > 0)) continue;
+    // Block-LEVEL box (block/list-item/flow-root/table, or a grid/flex CONTAINER — all margin-auto
+    // centreable), in normal flow, border-box. Inline-level boxes centre via text-align, not margins.
+    if (!/^(block|list-item|flow-root|table|grid|flex)$/.test(cs.display || "")) return false;
+    const pos = cs.position || "static";
+    if (pos !== "static" && pos !== "relative") return false;
+    if ((cs.float || "none") !== "none") return false;
+    if ((cs.boxSizing || "border-box") === "content-box") return false;
+    const maxW = cs.maxWidth || "";
+    if (!maxW.endsWith("px")) return false;               // must carry a px max-width cap at every band
+    const cap = pf(maxW);
+    if (!(cap > 0)) return false;
+    const content = pb.width - pf(pcs.paddingLeft) - pf(pcs.paddingRight) - pf(pcs.borderLeftWidth) - pf(pcs.borderRightWidth);
+    if (!(content > 0)) return false;
+    // The box sits at min(containerContent, cap): it fills the container below the cap and plateaus at
+    // the cap above it — the exact `width:100%; max-width:W` trajectory (NOT a fixed or content width).
+    if (Math.abs(nb.width - Math.min(content, cap)) > Math.max(1.5, 0.01 * nb.width)) return false;
+    const ml = pf(cs.marginLeft); const mr = pf(cs.marginRight);
+    // Where the container exceeds the cap there is room to centre — the box MUST be centred there
+    // (symmetric positive side margins), else it is left/right-aligned and margin:auto would move it.
+    if (content > cap + 4) {
+      if (ml > 1 && mr > 1 && Math.abs(ml - mr) <= 1.5) sawCenter = true;
+      else return false;
+    }
+    painted++;
+  }
+  return painted >= 2 && sawCenter;
+}
+
 function hasElementChild(node: IRNode): boolean {
   for (const c of node.children) if (!isTextChild(c)) return true;
   return false;
@@ -2948,7 +3504,7 @@ export function keyframesCss(ir: IR, assetMap: Map<string, string>, includeNode?
  *  per-node CSS emitter (generateCss) and the semantic class-map emitter (classMap.ts).
  *  `includeNode` scopes which nodes are emitted (multi-route shared layout) while still
  *  recursing so inheritance diffing against parents stays correct. */
-export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeNode?: (id: string) => boolean, colorVar?: (value: string) => string | null, tokenResolver?: TokenResolver, reflow = false): Map<string, NodeRule> {
+export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeNode?: (id: string) => boolean, colorVar?: (value: string) => string | null, tokenResolver?: TokenResolver, reflow = false, lottieMounts?: ReadonlySet<string>): Map<string, NodeRule> {
   const bands = computeBands(ir.doc.viewports, ir.doc.canonicalViewport);
   const baseVp = ir.doc.canonicalViewport;
   const rules = new Map<string, NodeRule>();
@@ -2957,7 +3513,7 @@ export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeN
   // per line so the line's free space — and thus sibling positions — is unchanged.
   const autoWidthFlex = new Set<string>();
 
-  const walk = (node: IRNode, parentNode: IRNode | undefined, parentFluid: boolean, layoutParent: IRNode | undefined, cbAncestor: IRNode | undefined, parentDefiniteHeight: boolean): void => {
+  const walk = (node: IRNode, parentNode: IRNode | undefined, parentFluid: boolean, layoutParent: IRNode | undefined, cbAncestor: IRNode | undefined, parentDefiniteHeight: boolean, standInVps: ReadonlySet<number> | null = null): void => {
     // Full-bleed fluidity propagates as a CONTIGUOUS chain from the root: a node is fluid
     // only if its containing block is also fluid — otherwise width:auto fills a fixed-width
     // ancestor instead of the viewport (a full-bleed row inside a fixed 1280 wrapper would
@@ -3003,9 +3559,15 @@ export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeN
     // parent, varies) OR the sizing probe measured that height:100% reproduces and auto does not
     // (heightProbeFills — direct ground truth, also catches constant fillers; inert pre-probe captures).
     const sourceFixedSize = !isContents && sourceFixedSizeIntent(node);
+    // Authored, geometry-corroborated fixed height/width on this node's own source class (banded or
+    // not). These break the fill↔content probe cycle that otherwise drops a banded authored height to
+    // `h-full` (logo tiles) or a shrink-0 box's authored width/height to auto (testimonial avatars):
+    // trust the baked per-band px the capture measured, exactly as the capture-side authored guard does.
+    const sourceFixedHeight = !isContents && sourceFixedHeightIntent(node, sampleVps);
+    const sourceFixedWidth = !isContents && sourceFixedWidthIntent(node, sampleVps);
     const mediaCover = !isContents && absoluteMediaCoversParent(node, parentNode, sampleVps);
     const absHeightFill = !isContents && absoluteHeightFill(node, parentNode, sampleVps);
-    const buttonFixedHeight = !isContents && (fixedHeightButtonLike(node, sampleVps) || sourceFixedSize);
+    const buttonFixedHeight = !isContents && (fixedHeightButtonLike(node, sampleVps) || sourceFixedSize || sourceFixedHeight);
     const heightFill = !isContents && !buttonFixedHeight && (isHeightFill(node, parentNode, parentDefiniteHeight, sampleVps) || absHeightFill || mediaCover || heightProbeFills(node, sampleVps));
     // This node's own height-drop decision, computed here so it can also feed childDefiniteHeight (a
     // height we drop becomes `auto` → does not confer a definite containing block). Same OR'd signals
@@ -3064,7 +3626,7 @@ export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeN
     const fillCap = !isContents ? fillsToCapWidth(node, parentNode, sampleVps) : null;
     // A width that leaves interior free space positions its children (auto margins / justify) — it's
     // load-bearing, so the content-sized branches below must NOT drop it (would kill the spacing).
-    const buttonFixedWidth = !isContents && (fixedWidthButtonLike(node, sampleVps) || sourceFixedSize);
+    const buttonFixedWidth = !isContents && (fixedWidthButtonLike(node, sampleVps) || sourceFixedSize || sourceFixedWidth);
     const lockWidth = !isContents && !fillCap && (hasInteriorFreeSpaceX(node, sampleVps) || buttonFixedWidth);
     // Ground-truth sizing probe is the primary signal after authored capped fills:
     // `width:100%; max-width:X` can look "auto" in a clone probe because the retained cap still
@@ -3082,6 +3644,7 @@ export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeN
     const mixedFill = (!lockWidth && !isContents && !percentVp) ? mixedFillByVp(node, parentNode, sampleVps) : null;
     const widthPlan: WidthPlan =
       fillCap ? { kind: "fillcap", cap: fillCap }
+      : sourceFixedWidth ? { kind: "fixed" }
       : sourceFixedSize ? inferred.plan
       : circularSlide ? { kind: "fixed" }
       : fullWidthSlide ? { kind: "basisFull" }
@@ -3103,20 +3666,45 @@ export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeN
       : inferred.plan;
     const centerAlways = inferred.centerAlways;
     const centeredAtAnySample = !!layoutParent && sampleVps.some((vp) => centeredAtVp(node, layoutParent, vp));
+    // A single-line text leaf sitting flush against its container's available width at every painted
+    // width → `white-space:nowrap` so a sub-pixel column shortfall in the clone can't wrap it. Decided
+    // once per node (uniform across bands); measured against layoutParent to see through contents wrappers.
+    const nowrapText = !isContents && nowrapWrapVulnerable(node, layoutParent, sampleVps);
+    // If this node has a NON-identity transform at any painted band, the identity `none` must be
+    // emitted at the bands that have it so the transform can't cascade across bands (freezing a
+    // width the source left untransformed). Identity matrices are canonicalized to "none" upstream.
+    let hasNonIdentityTransform = false, hasIdentityTransform = false;
+    for (const vp of sampleVps) {
+      const t = node.computedByVp[vp]?.transform;
+      if (t === undefined) continue;
+      if (t === "none") hasIdentityTransform = true;
+      else hasNonIdentityTransform = true;
+    }
+    const keepIdentityTransform = hasNonIdentityTransform && hasIdentityTransform;
     const stableCenter =
       centerAlways ||
       sourceMarginAutoIntent(node) ||
-      ((!!fillCap || hasPxMaxWidthCap(node, sampleVps)) && centeredAtAnySample);
+      ((!!fillCap || hasPxMaxWidthCap(node, sampleVps)) && centeredAtAnySample) ||
+      // A centred max-width container that is a flex/grid ITEM (which centerAlways / centeredAtVp bail
+      // on): `width:100%; max-width:W; margin:0 auto`. Safe because the px max-width cap is retained,
+      // so mx-auto only absorbs the centring slack. Handles per-viewport-varying caps.
+      isCappedCenteredContainer(node, parentNode, sampleVps);
     // Fluid grid-template-columns (fr), per-viewport (the column count may change across breakpoints).
     const gridColsByVp = fluidGridColumns(node, sampleVps);
     // Large one-row media grids need a definite height/aspect law before the single `1fr` row is
     // safe. Multi-row grids are handled by the older equal-track detector.
     const singleRowsByVp = !isContents ? singleFluidGridRow(node, sampleVps) : null;
-    const mediaGeometry = singleRowsByVp ? mediaHeightGeometry(node, sampleVps) : {};
+    // A lottie mount pins its captured height (replaced-like); it wins over the flow/media laws so the
+    // runtime player's aspect-sized svg fills a definite box instead of inflating past its neighbours.
+    const lottieHeight = !isContents && lottieMounts?.has(node.id) ? lottieMountHeight(node, sampleVps) : null;
+    const mediaGeometry = lottieHeight ? { heightByVp: lottieHeight } : singleRowsByVp ? mediaHeightGeometry(node, sampleVps) : {};
     const leftClampByVp = !isContents ? centeredInsetClamp(node, cbAncestor, sampleVps, "x") : null;
     const topClampByVp = !isContents ? centeredInsetClamp(node, cbAncestor, sampleVps, "y") : null;
-    const geometry: GeometryPlan = (mediaGeometry.heightByVp || mediaGeometry.aspectByVp || leftClampByVp || topClampByVp)
-      ? { ...mediaGeometry, ...(leftClampByVp ? { leftByVp: leftClampByVp } : {}), ...(topClampByVp ? { topByVp: topClampByVp } : {}) }
+    // Recover an authored viewport-relative min-height (`100vh`/`calc(100vh - Cpx)`) so a full-screen
+    // hero refills the window instead of freezing to the captured px at each band.
+    const minHeightByVp = !isContents ? viewportMinHeightLaw(node, sampleVps) : null;
+    const geometry: GeometryPlan = (mediaGeometry.heightByVp || mediaGeometry.aspectByVp || minHeightByVp || leftClampByVp || topClampByVp)
+      ? { ...mediaGeometry, ...(minHeightByVp ? { minHeightByVp } : {}), ...(leftClampByVp ? { leftByVp: leftClampByVp } : {}), ...(topClampByVp ? { topByVp: topClampByVp } : {}) }
       : GEOMETRY_NONE;
     // Fluid grid-template-rows (1fr) for equal, responsive, content-height-filling row regimes.
     const gridRowsByVp = fluidGridRows(node, sampleVps) ?? ((geometry.heightByVp || geometry.aspectByVp) ? singleRowsByVp : null);
@@ -3171,8 +3759,27 @@ export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeN
       dropInsets.delete("bottom");
       dropInsets.delete("left");
     }
-    const animOwned = animOwnedProps(node, baseVp); // opacity/transform driven by an infinite animation
-    const baseDecls = finalizeDecls(declsForViewport(node, parentNode?.computedByVp[baseVp], baseVp, assetMap, centeredBase, colorVar, ir.doc.perViewport[baseVp]?.scrollHeight, widthPlan, gridColsByVp?.get(baseVp), gridRowsByVp?.get(baseVp), flowH, dropInsets, leftPct, heightFill, geometry, dropGridRows, dropViewportMaxWidth), tokenResolver);
+    // opacity/transform driven by an infinite animation at the base OR any emitted band (a marquee
+    // gated to a breakpoint owns the transform only where it runs, but freezes a mid-scroll offset
+    // at the OTHER bands — suppress those frozen deltas at every width).
+    const animOwned = animOwnedProps(node, [baseVp, ...bands.map((b) => b.vp)]);
+    let baseDecls = finalizeDecls(declsForViewport(node, parentNode?.computedByVp[baseVp], baseVp, assetMap, centeredBase, colorVar, ir.doc.perViewport[baseVp]?.scrollHeight, widthPlan, gridColsByVp?.get(baseVp), gridRowsByVp?.get(baseVp), flowH, dropInsets, leftPct, heightFill, geometry, dropGridRows, dropViewportMaxWidth, nowrapText, keepIdentityTransform, sourceFixedHeight), tokenResolver);
+    // A node GRAFTED into the IR from a non-canonical capture (it does not exist in the canonical
+    // DOM, so it has no computed style at the base viewport → declsForViewport yields nothing).
+    // Its base rule must take it out of layout entirely; each band where it WAS observed then
+    // emits its full per-viewport decls as the delta (display is always emitted, so the band
+    // override both reveals and lays it out — the inverse of the canonical-only display:none band).
+    const absentAtBase = !node.computedByVp[baseVp];
+    if (absentAtBase) baseDecls = new Map([["display", "none"]]);
+    // Viewports where this node STANDS IN for divergent source content (content-identity drift on
+    // an ancestor): it has no captured data there, but the drift policy shows the canonical subtree
+    // instead of an empty shell — so its per-band hide must be skipped at those widths, and the
+    // stand-in state propagates to its descendants (they lack per-viewport data there too).
+    let driftStandIn: Set<number> | null = standInVps ? new Set([...standInVps].filter((vp) => !node.computedByVp[vp])) : null;
+    for (const vp of parentNode?.childDriftVps ?? []) {
+      if (!node.computedByVp[vp]) (driftStandIn ??= new Set()).add(vp);
+    }
+    if (driftStandIn && driftStandIn.size === 0) driftStandIn = null;
     const nr: NodeRule = { base: baseDecls, bands: [] };
 
     // Per-band overrides (delta vs base), using the parent's value AT THAT viewport.
@@ -3180,7 +3787,17 @@ export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeN
       if (!b.media) continue;
       // Node was not in the observed DOM at this width (responsive conditional
       // rendering): hide it so the clone matches the source at this viewport.
-      if (!node.computedByVp[b.vp]) { nr.bands.push({ media: b.media, decls: new Map([["display", "none"]]) }); continue; }
+      if (!node.computedByVp[b.vp]) {
+        // Grafted node: the base rule is already display:none — no per-band hide needed.
+        if (absentAtBase) continue;
+        // Content-identity drift (an ancestor's children were a wholly different set at this
+        // width): banding every canonical child display:none would render an EMPTY shell where
+        // the source showed content. Faithful-at-canonical: skip the hide and let the base
+        // (canonical) subtree stand in for the divergent set (recorded in doc.contentDrift).
+        if (driftStandIn?.has(b.vp)) continue;
+        nr.bands.push({ media: b.media, decls: new Map([["display", "none"]]) });
+        continue;
+      }
       // The node isn't PAINTED at this width. HOW it is hidden decides what to emit, because only
       // `display:none` takes the box out of layout — a `visibility:hidden` box still occupies space
       // and can extend the scrollable area. The base rule bakes CANONICAL geometry unconditionally,
@@ -3231,20 +3848,59 @@ export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeN
             if ((node.computedByVp[baseVp]?.display || "") !== "none") {
               nr.bands.push({ media: b.media, decls: new Map([["display", "none"]]) });
             }
+            continue;
           } else if (shownAtBase) {
-            // Hidden by an ancestor (or zero-size / opacity:0) but visible at base: geometry
-            // overrides are breakpoint noise — the ancestor's own hide (or the reveal replay,
-            // for scroll-reveal opacity) covers it. Emit only the hide the node itself carries.
-            const hide = new Map<string, string>();
-            if (pf(vpCs.opacity) === 0 && !animOwned.has("opacity")) hide.set("opacity", "0");
-            if (/^(hidden|collapse)$/.test(vpCs.visibility || "")) hide.set("visibility", "hidden");
-            if (hide.size) nr.bands.push({ media: b.media, decls: hide });
+            // The node is not painted here yet was not hidden by its own display:none / an
+            // ancestor's visibility (handled above). It can be (a) off-viewport / clipped — the
+            // walker marks a box invisible when `bbox.x >= vpW` — while still IN FLOW and
+            // OCCUPYING real layout space, or (b) genuinely suppressed (opacity:0 / visibility:hidden,
+            // typically a scroll-reveal or ancestor state that is breakpoint noise).
+            //
+            // Case (a) is load-bearing: an off-screen-right carousel slide is a display:block flex
+            // item that still sets its flex track's cross-size. The base rule bakes CANONICAL
+            // (desktop) geometry — a frozen desktop slide width/aspect inflates the mobile track
+            // (an off-screen `w-[285px]` slide dragging a 375px carousel to 532px). Same policy as
+            // the ownHidden / ancestor-hidden occupying-box paths above: fall through to the normal
+            // per-viewport delta so it sits at THIS width's measured geometry, not the baked canonical.
+            const bb = node.bboxByVp[b.vp];
+            const suppressed = pf(vpCs.opacity) === 0 || /^(hidden|collapse)$/.test(vpCs.visibility || "");
+            const inFlowHere = (vpCs.position || "static") === "static" || (vpCs.position || "static") === "relative";
+            if (!suppressed && inFlowHere && bb && (bb.width > 0 || bb.height > 0)) {
+              // Occupying, in-flow, merely off-viewport/clipped — fall through to the per-viewport delta.
+            } else {
+              // Suppressed (opacity:0 / visibility:hidden) but visible at base: geometry overrides are
+              // breakpoint noise — the ancestor's own hide (or the reveal replay, for scroll-reveal
+              // opacity) covers it. Emit only the hide the node itself carries.
+              const hide = new Map<string, string>();
+              if (pf(vpCs.opacity) === 0 && !animOwned.has("opacity")) hide.set("opacity", "0");
+              if (/^(hidden|collapse)$/.test(vpCs.visibility || "")) hide.set("visibility", "hidden");
+              if (hide.size) nr.bands.push({ media: b.media, decls: hide });
+              continue;
+            }
+          } else {
+            // Not painted here, not display:none, not ancestor-hidden, and NOT visible at base —
+            // an item that is off-viewport/clipped at EVERY captured width, base included (the
+            // walker marks a box invisible when `bbox.x >= vpW`). A carousel slide 6–12 that lives
+            // off-screen right at 1280 (the canonical base) as well as at 375/768 lands here. It is
+            // the identical load-bearing case as the shownAtBase occupying arm above: a display:block
+            // flex item that still sets its flex track's cross-size, so freezing the base rule's
+            // canonical (desktop) geometry inflates the mobile track. Run the same occupying-box test —
+            // in-flow, unsuppressed, non-zero bbox at THIS width → fall through to the per-viewport
+            // delta so it carries this width's measured geometry. A genuinely suppressed
+            // (opacity:0 / visibility:hidden) or zero-box node keeps the current skip.
+            const bb = node.bboxByVp[b.vp];
+            const suppressed = pf(vpCs.opacity) === 0 || /^(hidden|collapse)$/.test(vpCs.visibility || "");
+            const inFlowHere = (vpCs.position || "static") === "static" || (vpCs.position || "static") === "relative";
+            if (!suppressed && inFlowHere && bb && (bb.width > 0 || bb.height > 0)) {
+              // Occupying, in-flow, off-viewport at every width — fall through to the per-viewport delta.
+            } else {
+              continue;
+            }
           }
-          continue;
         }
       }
       const centeredVp = stableCenter || (layoutParent ? centeredAtVp(node, layoutParent, b.vp) : false);
-      const vpDecls = finalizeDecls(declsForViewport(node, parentNode?.computedByVp[b.vp], b.vp, assetMap, centeredVp, colorVar, ir.doc.perViewport[b.vp]?.scrollHeight, widthPlan, gridColsByVp?.get(b.vp), gridRowsByVp?.get(b.vp), flowH, dropInsets, leftPct, heightFill, geometry, dropGridRows, dropViewportMaxWidth), tokenResolver);
+      const vpDecls = finalizeDecls(declsForViewport(node, parentNode?.computedByVp[b.vp], b.vp, assetMap, centeredVp, colorVar, ir.doc.perViewport[b.vp]?.scrollHeight, widthPlan, gridColsByVp?.get(b.vp), gridRowsByVp?.get(b.vp), flowH, dropInsets, leftPct, heightFill, geometry, dropGridRows, dropViewportMaxWidth, nowrapText, keepIdentityTransform, sourceFixedHeight), tokenResolver);
       const delta = new Map<string, string>();
       for (const [k, v] of vpDecls) if (baseDecls.get(k) !== v) delta.set(k, v);
       for (const [k] of baseDecls) if (!vpDecls.has(k)) delta.set(k, resetValue(k));
@@ -3287,7 +3943,7 @@ export function collectNodeRules(ir: IR, assetMap: Map<string, string>, includeN
     }
     rules.set(node.id, nr);
 
-    for (const c of node.children) if (!isTextChild(c)) walk(c, node, childFluid, childLayoutParent, childCb, childDefiniteHeight);
+    for (const c of node.children) if (!isTextChild(c)) walk(c, node, childFluid, childLayoutParent, childCb, childDefiniteHeight, driftStandIn);
   };
   // The root's containing block is the viewport-filling <html>, so it starts the fluid chain.
   walk(ir.root, undefined, true, undefined, undefined, false);
diff --git a/compiler/src/generate/interactive.ts b/compiler/src/generate/interactive.ts
index 0b849d1..fdba181 100644
--- a/compiler/src/generate/interactive.ts
+++ b/compiler/src/generate/interactive.ts
@@ -151,7 +151,7 @@ export function accordionJsx(specs: AccordionRuntimeSpec[], indent: number): str
 }
 
 export const ACCORDION_TSX = `"use client";
-import { useEffect, useRef } from "react";
+import { useEffect } from "react";
 
 type CapStyle = Record<string, string>;
 type RTAcc = { trigger: string; region: string; expanded: boolean; triggerOn: CapStyle; triggerOff: CapStyle; regionShown: CapStyle; regionHidden: CapStyle };
@@ -167,10 +167,9 @@ function applyStyle(el: HTMLElement | null, s: CapStyle) {
 /** Wires captured accordion rows with small explicit state.
  *  Hydration initializes the captured base state, then clicks toggle only the target row. */
 export default function Accordion({ specs }: { specs: AccordionSpec[] }) {
-  const wired = useRef(false);
   useEffect(() => {
-    if (wired.current) return;
-    wired.current = true;
+    const ac = new AbortController();
+    const { signal } = ac;
     for (const spec of specs) {
       const state = spec.items.map((it) => it.expanded);
       const renderItem = (i: number) => {
@@ -193,10 +192,11 @@ export default function Accordion({ specs }: { specs: AccordionSpec[] }) {
           e.preventDefault();
           state[i] = !state[i];
           renderItem(i);
-        });
+        }, { signal });
         renderItem(i);
       });
     }
+    return () => ac.abort();
   }, [specs]);
   return null;
 }
@@ -204,7 +204,7 @@ export default function Accordion({ specs }: { specs: AccordionSpec[] }) {
 
 /** The fixed DittoWire client component, written once per generated app. */
 export const DITTO_WIRE_TSX = `"use client";
-import { useEffect, useRef } from "react";
+import { useEffect } from "react";
 
 type CapStyle = Record<string, string>;
 type RTTab = { trigger: string; panel: string; triggerOn: CapStyle; triggerOff: CapStyle; panelShown: CapStyle; panelHidden: CapStyle; descendants?: Record<string, CapStyle> };
@@ -235,10 +235,9 @@ function applyDesc(d?: Record<string, CapStyle>) {
  *  on mount: the server-rendered markup + per-node CSS already reproduce the captured
  *  base state exactly, so state styles are applied only on user interaction. */
 export default function DittoWire({ spec }: { spec: Spec }) {
-  const wired = useRef(false);
   useEffect(() => {
-    if (wired.current) return;
-    wired.current = true;
+    const ac = new AbortController();
+    const { signal } = ac;
     if (spec.kind === "tabs") {
       let active = spec.active;
       const render = () => spec.tabs.forEach((t, i) => {
@@ -254,7 +253,7 @@ export default function DittoWire({ spec }: { spec: Spec }) {
       spec.tabs.forEach((t, i) => {
         const trig = byCid(t.trigger);
         if (!trig) return;
-        trig.addEventListener("click", (e) => { e.preventDefault(); active = i; render(); });
+        trig.addEventListener("click", (e) => { e.preventDefault(); active = i; render(); }, { signal });
         trig.addEventListener("keydown", (e) => {
           const k = (e as KeyboardEvent).key;
           if (k === "ArrowRight" || k === "ArrowLeft") {
@@ -263,7 +262,7 @@ export default function DittoWire({ spec }: { spec: Spec }) {
             render();
             byCid(spec.tabs[active].trigger)?.focus();
           }
-        });
+        }, { signal });
       });
       // No initial render() — the static base state is already correct.
     } else if (spec.kind === "accordion") {
@@ -278,7 +277,7 @@ export default function DittoWire({ spec }: { spec: Spec }) {
       };
       spec.items.forEach((it, i) => {
         const trig = byCid(it.trigger);
-        if (trig) trig.addEventListener("click", (e) => { e.preventDefault(); state[i] = !state[i]; renderItem(i); });
+        if (trig) trig.addEventListener("click", (e) => { e.preventDefault(); state[i] = !state[i]; renderItem(i); }, { signal });
       });
       // No initial renderItem — the static base state is already correct.
     } else if (spec.kind === "carousel") {
@@ -293,9 +292,9 @@ export default function DittoWire({ spec }: { spec: Spec }) {
       };
       const nextEl = spec.next ? byCid(spec.next) : null;
       const prevEl = spec.prev ? byCid(spec.prev) : null;
-      nextEl?.addEventListener("click", (e) => { e.preventDefault(); go(index + 1); });
-      prevEl?.addEventListener("click", (e) => { e.preventDefault(); go(index - 1); });
-      spec.bullets.forEach((b, bi) => byCid(b)?.addEventListener("click", (e) => { e.preventDefault(); go(bi); }));
+      nextEl?.addEventListener("click", (e) => { e.preventDefault(); go(index + 1); }, { signal });
+      prevEl?.addEventListener("click", (e) => { e.preventDefault(); go(index - 1); }, { signal });
+      spec.bullets.forEach((b, bi) => byCid(b)?.addEventListener("click", (e) => { e.preventDefault(); go(bi); }, { signal }));
       // No initial go() — the static base state is already correct.
     } else {
       // Disclosure: dropdown / mega-menu / modal — a trigger reveals a hidden overlay.
@@ -311,18 +310,19 @@ export default function DittoWire({ spec }: { spec: Spec }) {
           if (o) applyDesc(it.descendants);
           if (o) panel.removeAttribute("hidden"); else panel.setAttribute("hidden", "");
         };
-        trig.addEventListener("click", (e) => { e.preventDefault(); set(it.isDialog ? true : !open); });
+        trig.addEventListener("click", (e) => { e.preventDefault(); set(it.isDialog ? true : !open); }, { signal });
         if (it.hoverOpen) {
           const root = trig.parentElement ?? trig;
-          root.addEventListener("mouseenter", () => set(true));
-          root.addEventListener("mouseleave", () => set(false));
+          root.addEventListener("mouseenter", () => set(true), { signal });
+          root.addEventListener("mouseleave", () => set(false), { signal });
         }
-        it.closes.forEach((c) => byCid(c)?.addEventListener("click", (e) => { e.preventDefault(); set(false); }));
-        if (it.backdropClose) panel.addEventListener("click", (e) => { if (e.target === panel) set(false); });
-        document.addEventListener("keydown", (e) => { if ((e as KeyboardEvent).key === "Escape" && open) set(false); });
+        it.closes.forEach((c) => byCid(c)?.addEventListener("click", (e) => { e.preventDefault(); set(false); }, { signal }));
+        if (it.backdropClose) panel.addEventListener("click", (e) => { if (e.target === panel) set(false); }, { signal });
+        document.addEventListener("keydown", (e) => { if ((e as KeyboardEvent).key === "Escape" && open) set(false); }, { signal });
       });
       // No initial set() — the static base state is already correct.
     }
+    return () => ac.abort();
   }, [spec]);
   return null;
 }
diff --git a/compiler/src/generate/lottie.ts b/compiler/src/generate/lottie.ts
index 7eeb49d..d27b17a 100644
--- a/compiler/src/generate/lottie.ts
+++ b/compiler/src/generate/lottie.ts
@@ -126,7 +126,7 @@ const byCid = (cid: string): HTMLElement | null => document.querySelector('[data
 export default function DittoLottie({ spec }: { spec: LottieSpec }) {
   useEffect(() => {
     const stopped = (window as any).__dittoMotionStopped === true;
-    const anims: Array<{ destroy: () => void; goToAndStop: (value: number, isFrame?: boolean) => void }> = [];
+    const anims: Array<{ destroy: () => void; goToAndStop: (value: number, isFrame?: boolean) => void; addEventListener: (name: string, cb: () => void) => void }> = [];
     let cancelled = false;
     void (async () => {
       const lottie = (await import("lottie-web")).default;
@@ -134,17 +134,59 @@ export default function DittoLottie({ spec }: { spec: LottieSpec }) {
       for (const it of spec.items) {
         const el = byCid(it.cid);
         if (!el) continue;
-        // clear the captured placeholder frame so it never stacks with the live render
-        el.innerHTML = "";
         try {
+          // Mount the live animation into an OVERLAY child, keeping the captured placeholder
+          // frame in the DOM until lottie signals a successful load — a failed load (bad JSON,
+          // network) then leaves the placeholder intact instead of erasing the container to blank.
+          // The overlay stays position:absolute;inset:0 for its WHOLE life (not just pre-swap):
+          // the host box carries the captured per-viewport height, and only an absolutely-filled
+          // overlay inherits that definite box. A static-flow overlay has indefinite height, so
+          // the player's svg (style height:100%) collapses to auto and inflates to the source
+          // aspect (a portrait viewBox then oversizes far past the captured, letterboxed box).
+          const mount = document.createElement("div");
+          mount.style.position = "absolute";
+          mount.style.inset = "0";
+          mount.style.opacity = "0";
+          const cs = getComputedStyle(el);
+          if (cs.position === "static") el.style.position = "relative";
+          // Mark the host so emitted CSS can force the runtime svg/canvas to fit the pinned box.
+          el.setAttribute("data-ditto-lottie", "");
+          el.appendChild(mount);
           const anim = lottie.loadAnimation({
-            container: el,
+            container: mount,
             renderer: it.renderer === "canvas" ? "canvas" : "svg",
             loop: it.loop,
             autoplay: it.autoplay && !stopped,
             ...(it.path ? { path: it.path } : { animationData: it.animationData as object }),
             rendererSettings: { preserveAspectRatio: "xMidYMid meet" },
           });
+          // Swap only once the animation is genuinely ready: reveal the live render and remove
+          // every original child (the placeholder) so the two never stack. Before discarding the
+          // placeholder, forward its data-cid onto the runtime-rendered svg/canvas so the media
+          // node stays addressable by cid after the swap (it would otherwise mount without one).
+          const reveal = () => {
+            mount.style.opacity = "1";
+            // The captured placeholder is an svg/canvas (or wraps one) carrying its own data-cid.
+            let placeholderCid: string | null = null;
+            for (const child of Array.from(el.childNodes)) {
+              if (child === mount || placeholderCid !== null || !(child instanceof Element)) continue;
+              const media = child.matches("svg, canvas") ? child : child.querySelector("svg, canvas");
+              placeholderCid = (media ?? child).getAttribute("data-cid");
+            }
+            for (const child of Array.from(el.childNodes)) if (child !== mount) el.removeChild(child);
+            if (placeholderCid) {
+              const rendered = mount.querySelector("svg, canvas");
+              if (rendered) rendered.setAttribute("data-cid", placeholderCid);
+            }
+            // Do NOT clear position/inset: the overlay must keep filling the host's pinned box
+            // (see above). Stripping them reverts it to static flow → indefinite height → the
+            // player's height:100% svg inflates to its aspect and escapes the captured bbox.
+          };
+          // DOMLoaded fires only after the JSON parsed and the first frame rendered — the
+          // right moment to reveal the live render and drop the placeholder. data_failed
+          // (bad JSON / fetch error) tears the empty mount back out, leaving the placeholder.
+          anim.addEventListener("DOMLoaded", reveal);
+          anim.addEventListener("data_failed", () => { try { el.removeChild(mount); } catch {} });
           if (stopped) { try { anim.goToAndStop(0, true); } catch {} }
           anims.push(anim);
         } catch {
diff --git a/compiler/src/generate/manifest.ts b/compiler/src/generate/manifest.ts
index 2eb8071..5c65b48 100644
--- a/compiler/src/generate/manifest.ts
+++ b/compiler/src/generate/manifest.ts
@@ -56,6 +56,13 @@ export function buildManifest(args: {
       fallback: fontGraph.entries.filter((f) => f.status === "fallback").length,
     },
     components: { count: componentCount },
+    // Fidelity note: containers whose children were a DIFFERENT SET at some band viewport(s)
+    // (content-identity drift — the source deterministically served other content there). The
+    // clone shows the canonical-viewport children at those widths (faithful-at-canonical) instead
+    // of an empty shell; a perceptual delta against the source at those widths is expected.
+    divergence: {
+      contentDrift: (ir.doc.contentDrift ?? []).map((d) => ({ id: d.id, tag: d.tag, viewports: d.viewports })),
+    },
     // Stage 2: capture-sanity audit — what overlays were dismissed, whether any
     // still covered the page, video stills materialized, and per-viewport quiescence.
     capture: {
diff --git a/compiler/src/generate/menu.ts b/compiler/src/generate/menu.ts
index e2acb61..e1e2df9 100644
--- a/compiler/src/generate/menu.ts
+++ b/compiler/src/generate/menu.ts
@@ -94,7 +94,7 @@ export function dropdownMenuImportPath(depth: number): string {
 
 /** The fixed DropdownMenu client component, written once per generated app. */
 export const DROPDOWN_MENU_TSX = `"use client";
-import { useEffect, useRef } from "react";
+import { useEffect } from "react";
 
 type RTMenu = { trigger: string; hoverOpen: boolean; gap: number; align: "left" | "right"; html: string };
 const byCid = (cid: string): HTMLElement | null => document.querySelector('[data-cid="' + cid + '"]');
@@ -103,10 +103,10 @@ const byCid = (cid: string): HTMLElement | null => document.querySelector('[data
  *  user interaction does it inject the captured panel fragment under its trigger. The base
  *  render is therefore unchanged. */
 export default function DropdownMenu({ menus }: { menus: RTMenu[] }) {
-  const wired = useRef(false);
   useEffect(() => {
-    if (wired.current) return;
-    wired.current = true;
+    const ac = new AbortController();
+    const { signal } = ac;
+    const openPanels: HTMLElement[] = [];
     for (const m of menus) {
       const trig = byCid(m.trigger);
       if (!trig) continue;
@@ -127,27 +127,41 @@ export default function DropdownMenu({ menus }: { menus: RTMenu[] }) {
         panel = wrap.firstElementChild as HTMLElement | null;
         if (!panel) return;
         document.body.appendChild(panel);
+        openPanels.push(panel);
         place();
         trig.setAttribute("aria-expanded", "true");
       };
-      const close = () => { if (panel) { panel.remove(); panel = null; } trig.setAttribute("aria-expanded", "false"); };
+      const close = () => {
+        if (panel) {
+          const i = openPanels.indexOf(panel);
+          if (i !== -1) openPanels.splice(i, 1);
+          panel.remove();
+          panel = null;
+        }
+        trig.setAttribute("aria-expanded", "false");
+      };
       const toggle = () => (panel ? close() : open());
       if (m.hoverOpen) {
         const root = trig.parentElement ?? trig;
-        root.addEventListener("mouseenter", open);
-        root.addEventListener("mouseleave", close);
+        root.addEventListener("mouseenter", open, { signal });
+        root.addEventListener("mouseleave", close, { signal });
       } else {
-        trig.addEventListener("click", (e) => { e.preventDefault(); toggle(); });
+        trig.addEventListener("click", (e) => { e.preventDefault(); toggle(); }, { signal });
       }
-      document.addEventListener("keydown", (e) => { if (e.key === "Escape") close(); });
+      document.addEventListener("keydown", (e) => { if (e.key === "Escape") close(); }, { signal });
       document.addEventListener("click", (e) => {
         const t = e.target as Node;
         if (panel && !trig.contains(t) && !panel.contains(t)) close();
-      });
-      window.addEventListener("resize", place);
-      window.addEventListener("scroll", place, { passive: true });
+      }, { signal });
+      window.addEventListener("resize", place, { signal });
+      window.addEventListener("scroll", place, { passive: true, signal });
     }
     (window as any).__dittoMenuReady = true; // wiring done — lets the gate drive deterministically
+    return () => {
+      ac.abort();
+      // Remove any still-open panels appended to document.body so unmount leaves no orphan nodes.
+      for (const p of openPanels.splice(0)) p.remove();
+    };
   }, [menus]);
   return null;
 }
diff --git a/compiler/src/generate/motion.ts b/compiler/src/generate/motion.ts
index 967e74f..4701a90 100644
--- a/compiler/src/generate/motion.ts
+++ b/compiler/src/generate/motion.ts
@@ -41,12 +41,31 @@ function capToCid(ir: IR): Map<string, string> {
   return m;
 }
 
+/** Map every IR node's cid → node, so an emission guard can inspect the resolved target. */
+function cidToNode(ir: IR): Map<string, IRNode> {
+  const m = new Map<string, IRNode>();
+  const walk = (n: IRNode): void => {
+    m.set(n.id, n);
+    for (const c of n.children) if (!isTextChild(c)) walk(c);
+  };
+  walk(ir.root);
+  return m;
+}
+
+/** True when an IR node has ≥1 element child. A genuine rotating word/phrase is a text leaf
+ *  (no element children); a container captured as a rotator would have the runtime flatten its
+ *  whole subtree to one text node, destroying every descendant element. */
+function hasElementChild(n: IRNode | undefined): boolean {
+  return !!n && n.children.some((c) => !isTextChild(c));
+}
+
 /** Resolve cap-keyed motion specs to cids that survived into this IR (optionally
  *  scoped by an include filter, for multi-route body/chrome splitting). Specs whose
  *  element was pruned are dropped (left static). */
 export function buildMotionSpec(ir: IR, motion: MotionCapture | undefined, include?: (cid: string) => boolean): MotionSpec {
   if (!motion) return { waapi: [], rotators: [], reveals: [], marquees: [] };
   const map = capToCid(ir);
+  const nodeByCid = cidToNode(ir);
   const ok = (cid: string | undefined): cid is string => !!cid && (!include || include(cid));
   const waapi: RTWaapi[] = [];
   for (const w of motion.waapi as WaapiAnim[]) {
@@ -58,6 +77,11 @@ export function buildMotionSpec(ir: IR, motion: MotionCapture | undefined, inclu
   for (const r of motion.rotators as RotatorSpec[]) {
     const cid = map.get(r.cap);
     if (!ok(cid)) continue;
+    // A rotator cycles the text of a single leaf word/phrase. If the resolved target has element
+    // children, capture misclassified a structural container (e.g. one whose rows were injected at
+    // runtime, uncapped, after cid-cap tagging) as a rotator. Emitting it would let the runtime
+    // flatten every descendant element to one text node; drop it so the static subtree survives.
+    if (hasElementChild(nodeByCid.get(cid))) continue;
     rotators.push({ cid, texts: r.texts, intervalMs: r.intervalMs });
   }
   const reveals: RTReveal[] = [];
@@ -157,7 +181,7 @@ export default function DittoMotion({ spec }: { spec: MotionSpec }) {
   useEffect(() => {
     if ((window as any).__dittoMotionStopped) return; // measurement mode — apply nothing
     const intervals: ReturnType<typeof setInterval>[] = [];
-    const rotators: Array<{ el: HTMLElement; original: string | null }> = [];
+    const rotators: Array<{ el: HTMLElement; original: Node[] }> = [];
     const anims: Animation[] = [];
     // per-reveal "show now" fns (also the cleanup); animate=false jumps to the settled frame
     const revealed: Array<(animate: boolean) => void> = [];
@@ -196,8 +220,15 @@ export default function DittoMotion({ spec }: { spec: MotionSpec }) {
     for (const r of spec.rotators) {
       const el = byCid(r.cid);
       if (!el || r.texts.length < 2) continue;
-      const original = el.textContent;
-      const start = r.texts.findIndex((t) => t === (original || "").replace(/\\s+/g, " ").trim());
+      // Defense in depth: a genuine rotating word is a text leaf. If the target has element
+      // children, it was misclassified (its subtree would be destroyed by a text write) — skip it
+      // so the static structure survives even if the emission guard was bypassed.
+      if (el.childElementCount > 0) continue;
+      // Save the ORIGINAL child nodes (cloned) rather than a flattened textContent string, so the
+      // settle/restore path rebuilds the exact subtree via replaceChildren — never a lossy text
+      // node. For a real text leaf this is just the single text node round-tripped intact.
+      const original = Array.from(el.childNodes).map((n) => n.cloneNode(true));
+      const start = r.texts.findIndex((t) => t === (el.textContent || "").replace(/\\s+/g, " ").trim());
       let i = start < 0 ? 0 : start;
       rotators.push({ el, original });
       intervals.push(setInterval(() => { i = (i + 1) % r.texts.length; el.textContent = r.texts[i]!; }, Math.max(400, r.intervalMs)));
@@ -274,7 +305,7 @@ export default function DittoMotion({ spec }: { spec: MotionSpec }) {
     const stopAll = () => {
       (window as any).__dittoMotionStopped = true;
       for (const id of intervals) clearInterval(id);
-      for (const r of rotators) r.el.textContent = r.original;
+      for (const r of rotators) r.el.replaceChildren(...r.original.map((n) => n.cloneNode(true)));
       for (const a of anims) { try { a.cancel(); } catch { /* ignore */ } }
       if (io) io.disconnect();
       if (forceTimer) clearTimeout(forceTimer);
diff --git a/compiler/src/generate/sectionSplit.ts b/compiler/src/generate/sectionSplit.ts
index f209ca7..7ae5e92 100644
--- a/compiler/src/generate/sectionSplit.ts
+++ b/compiler/src/generate/sectionSplit.ts
@@ -15,6 +15,7 @@
 import type { IR, IRNode } from "../normalize/ir.js";
 import { isTextChild } from "../normalize/ir.js";
 import type { RecipeCandidate, RecipeKind, RecipeReport } from "../infer/recipes.js";
+import { detectSectionNodes, heroLikeHeader } from "../infer/sections.js";
 import { subtreeSignature } from "../site/sharedLayout.js";
 
 export type SectionPlan = {
@@ -23,7 +24,7 @@ export type SectionPlan = {
 };
 
 const MIN_SECTION_H = 56;
-const MAX_SECTIONS = 24;
+const MAX_SECTIONS = 32;
 
 function box(n: IRNode, cw: number): { width: number; height: number } | undefined {
   return n.bboxByVp[cw] ?? Object.values(n.bboxByVp)[0];
@@ -31,15 +32,9 @@ function box(n: IRNode, cw: number): { width: number; height: number } | undefin
 function yOf(n: IRNode, cw: number): number {
   return (n.bboxByVp[cw] ?? Object.values(n.bboxByVp)[0])?.y ?? 0;
 }
-function visible(n: IRNode, cw: number): boolean {
-  return !!(n.visibleByVp[cw] ?? Object.values(n.visibleByVp)[0]);
-}
 function elementChildren(n: IRNode): IRNode[] {
   return n.children.filter((c): c is IRNode => !isTextChild(c));
 }
-function significantChildren(n: IRNode, cw: number): IRNode[] {
-  return elementChildren(n).filter((c) => visible(c, cw) && (box(c, cw)?.height ?? 0) >= MIN_SECTION_H);
-}
 
 function subtreeHasTag(n: IRNode, tag: string, depth = 4): boolean {
   if (depth < 0) return false;
@@ -105,6 +100,83 @@ function identName(name: string): string {
   return /^[A-Za-z_$]/.test(name) ? name : "S" + name;
 }
 
+// Generic structural words that carry no section identity — dropped from source-derived names.
+const GENERIC_NAME_WORDS = new Set([
+  "section", "sections", "wrapper", "container", "block", "blocks", "template", "templates",
+  "group", "inner", "outer", "content", "contents", "row", "col", "column", "grid", "layout",
+  "shopify", "js", "tvg", "elementor", "wp", "widget", "module", "region", "main", "page",
+  "component", "components", "el", "root", "body", "area", "box", "item", "items", "wrap",
+]);
+
+/** A trailing token looks like a build hash (mixed-case or long alnum entropy, e.g.
+ *  `JtTWTt`, `RbEALJ`, `x19f2a`, `dDMm2q`) rather than a real word — strip it. A token is
+ *  hashy when it is ≥4 chars and either mixes upper+lower case or is a long digit-bearing run. */
+function looksHashy(tok: string): boolean {
+  if (tok.length < 4) return false;
+  const hasUpper = /[A-Z]/.test(tok), hasLower = /[a-z]/.test(tok), hasDigit = /\d/.test(tok);
+  if (hasUpper && hasLower) return true;                 // camel/entropy hash: JtTWTt, dDMm2q
+  if (hasDigit && tok.length >= 6) return true;          // long id run: 19797275672650
+  if (!/[aeiou]/i.test(tok) && tok.length >= 5) return true; // vowelless run: bcdfgh
+  return false;
+}
+
+/** Turn a source id/class token stream into ≤3 semantic PascalCase words, or "" when the
+ *  evidence is all-generic or hashy. Strips CMS prefixes (shopify-section-…__), leading
+ *  numeric template ids, generic structural words, and trailing hash suffixes. Exported for
+ *  tests (the hashy-suffix stripping + generic-word filtering is the load-bearing part). */
+export function nameFromSourceToken(raw: string): string {
+  // Peel known CMS section-id prefixes, keeping the semantic slug after `__` / the hook name.
+  // Case is preserved through prefix-stripping + tokenizing so `looksHashy` can see the
+  // mixed-case entropy of build hashes (RbEALJ, JtTWTt) BEFORE we normalize to lowercase.
+  const s = raw.trim()
+    .replace(/^shopify-section-(?:template|sections)--\d+__/i, "")
+    .replace(/^shopify-(?:section|block)-/i, "")
+    .replace(/^(?:js|tvg|elementor|wp|et|elementor-element)[-_]/i, "");
+  const tokens = s.split(/[\s\-_]+/).filter(Boolean);
+  const kept: string[] = [];
+  for (const t of tokens) {
+    if (kept.length >= 3) break;
+    if (/^\d+$/.test(t)) continue;                  // pure numeric template ids
+    if (GENERIC_NAME_WORDS.has(t.toLowerCase())) continue; // structural noise
+    if (looksHashy(t)) continue;                    // trailing entropy suffix (mixed-case aware)
+    if (t.length < 2) continue;
+    const lc = t.toLowerCase();
+    kept.push(lc[0]!.toUpperCase() + lc.slice(1));
+  }
+  return kept.join("");
+}
+
+// A source `id` (or `data-section-type`) is a DELIBERATE, developer-authored block name only
+// when it carries a recognized CMS section prefix — Shopify's `shopify-section-…__split_callout`,
+// or a generic `section-…`/`…-section`. Arbitrary utility classes (`g_section_space`,
+// `duraldar-cta_section`) are styling noise, so we do NOT mine class names — a truncated heading
+// slug reads better than a made-up name. `js-*` behaviour hooks ARE intentional and allowed.
+const CMS_SECTION_ID = /shopify-section|^section[-_]|[-_]section(?:[-_]|$)|data-section/i;
+
+/** Best semantic name derivable from a section subtree's source *ids* + `js-*` hooks — the
+ *  only source signals reliable enough to beat a heading slug. Scans the root + shallow
+ *  descendants. Returns "" when no trustworthy semantic evidence exists. */
+function sourceNameForSection(sec: IRNode): string {
+  const candidates: string[] = [];
+  const collect = (n: IRNode, depth: number): void => {
+    const id = n.attrs.id;
+    if (id && CMS_SECTION_ID.test(id)) candidates.push(id);
+    const sectionType = n.attrs["data-section-type"] ?? n.attrs["data-section"];
+    if (sectionType) candidates.push(sectionType);
+    if (n.srcClass) {
+      // Only explicit `js-…` behaviour hooks — a deliberate semantic handle, not a utility class.
+      for (const cls of n.srcClass.split(/\s+/)) if (/^js[-_][a-z]/i.test(cls)) candidates.push(cls);
+    }
+    if (depth > 0) for (const c of elementChildren(n)) collect(c, depth - 1);
+  };
+  collect(sec, 2);
+  for (const c of candidates) {
+    const name = nameFromSourceToken(c);
+    if (name && name.length >= 3) return name;
+  }
+  return "";
+}
+
 function looksLikeNav(n: IRNode, cw: number): boolean {
   if (n.tag === "nav" || n.tag === "header") return true;
   if (subtreeHasTag(n, "nav")) return true;
@@ -225,18 +297,11 @@ function recipeFallbackSections(ir: IR, recipes?: RecipeReport): { sections: IRN
 
 export function planSections(ir: IR, recipes?: RecipeReport): SectionPlan {
   const cw = ir.doc.canonicalViewport;
-  // Descend through the wrapper chain (single significant child) to the container
-  // whose children are the actual sections.
-  let node = ir.root;
-  for (let i = 0; i < 10; i++) {
-    const sig = significantChildren(node, cw);
-    if (sig.length >= 2) break;
-    if (sig.length === 1) { node = sig[0]!; continue; }
-    const kids = elementChildren(node);
-    if (kids.length === 1) { node = kids[0]!; continue; }
-    break;
-  }
-  // Exclude any child that is part of a REPEATED run (≥3 same-signature siblings): that's
+  const pageH = ir.doc.perViewport[cw]?.scrollHeight ?? 0;
+  // The shared recursive band decomposition (infer/sections) — the same roots the
+  // section gate validates, so each emitted file corresponds to a gate section.
+  const bands = detectSectionNodes(ir).filter((n) => n.id !== ir.root.id);
+  // Exclude any band that is part of a REPEATED run (≥3 same-signature siblings): that's
   // a component cluster (a card/logo grid), which component extraction should turn into a
   // `.map()` over a data array — not a wall of near-identical "section" files. Only the
   // distinct, one-off blocks become sections.
@@ -246,29 +311,14 @@ export function planSections(ir: IR, recipes?: RecipeReport): SectionPlan {
     return list.filter((s) => (count.get(subtreeSignature(s)) ?? 0) < 3);
   };
 
-  let candidates = significantChildren(node, cw);
-  let sections = distinctOf(candidates);
-  const fallback = recipeFallbackSections(ir, recipes);
-  // If the container yields too few sections, a dominant child is a wrapper (e.g. <main>)
-  // holding the real sections — expand such oversized children into their own significant
-  // children, keeping the other siblings (e.g. a sibling <footer>). Gated on <3 so a page
-  // that already splits cleanly is untouched.
-  if (sections.length < 3) {
-    const pageH = ir.doc.perViewport[cw]?.scrollHeight ?? 0;
-    const expanded: IRNode[] = [];
-    for (const c of candidates) {
-      const inner = significantChildren(c, cw);
-      const h = box(c, cw)?.height ?? 0;
-      if (inner.length >= 3 && pageH > 0 && h >= pageH * 0.4) expanded.push(...inner);
-      else expanded.push(c);
-    }
-    candidates = expanded;
-    sections = distinctOf(candidates);
-  }
+  let sections = distinctOf(bands);
   let recipeNameHints = new Map<string, string>();
-  if (sections.length < 3 && fallback.sections.length >= 3) {
-    sections = fallback.sections;
-    recipeNameHints = fallback.names;
+  if (sections.length < 3) {
+    const fallback = recipeFallbackSections(ir, recipes);
+    if (fallback.sections.length >= 3) {
+      sections = fallback.sections;
+      recipeNameHints = fallback.names;
+    }
   }
   const roots = new Map<string, string>();
   if (sections.length < 3 || sections.length > MAX_SECTIONS) return { roots };
@@ -280,6 +330,10 @@ export function planSections(ir: IR, recipes?: RecipeReport): SectionPlan {
     return n === 1 ? base : `${base}${n}`;
   };
 
+  // Hero must actually start near the top of the page; without the gate a
+  // mid-page band inherits the name when the true hero was excluded (e.g. as a
+  // repeated run), which is worse than an honest content-derived name.
+  const heroMaxY = Math.max(900, pageH * 0.25);
   let heroAssigned = false;
   sections.forEach((sec, i) => {
     const isLast = i === sections.length - 1;
@@ -287,18 +341,31 @@ export function planSections(ir: IR, recipes?: RecipeReport): SectionPlan {
     let name: string;
     if (sec.tag === "footer" || (isLast && looksLikeNav(sec, cw) === false && subtreeHasTag(sec, "a") && (box(sec, cw)?.height ?? 0) < 700)) {
       name = sec.tag === "footer" ? "Footer" : (titleText(sec) ? slugWords(titleText(sec)) + "Section" : "Footer");
-    } else if (i === 0 && looksLikeNav(sec, cw)) {
+    } else if (sec.tag === "nav"
+      || (i === 0 && looksLikeNav(sec, cw) && !heroLikeHeader(sec, cw))
+      // a thin fixed bar wrapping the real <nav> (often a styled <div>, sorted after
+      // the hero it overlays) is still the navbar
+      || (yOf(sec, cw) <= 160 && (box(sec, cw)?.height ?? 0) <= 160 && subtreeHasTag(sec, "nav"))) {
       name = "Navbar";
-    } else if (sec.tag === "header") {
+    } else if (sec.tag === "header" && !heroLikeHeader(sec, cw)) {
+      // a <header> carrying the page h1 at real height is the hero, not chrome
       name = "Header";
-    } else if (!heroAssigned) {
+    } else if (!heroAssigned && yOf(sec, cw) <= heroMaxY) {
       heroAssigned = true;
       name = "HeroSection";
     } else if (recipeName) {
       name = recipeName;
     } else {
+      // Prefer a clean semantic name from the source markup (Shopify/CMS section ids +
+      // `js-*` hooks, hash suffixes stripped) over a truncated heading slug — the source
+      // slug (`split_callout` → SplitCalloutSection) reads more like a hand-authored name.
+      const sourceName = sourceNameForSection(sec);
       const slug = slugWords(titleText(sec));
-      name = slug ? `${slug}Section` : `Section${i + 1}`;
+      name = sourceName ? `${sourceName}Section`
+        : slug ? `${slug}Section`
+        : subtreeHasTag(sec, "form", 6) ? "ContactSection"
+        : subtreeHasTag(sec, "video", 6) || subtreeHasTag(sec, "iframe", 6) ? "MediaSection"
+        : `Section${i + 1}`;
     }
     roots.set(sec.id, dedupe(identName(name)));
   });
diff --git a/compiler/src/generate/seo.ts b/compiler/src/generate/seo.ts
index 1227f4c..891e128 100644
--- a/compiler/src/generate/seo.ts
+++ b/compiler/src/generate/seo.ts
@@ -289,8 +289,15 @@ function metadataObject(report: SeoInventory): Record<string, unknown> {
   if (keywords) metadata.keywords = keywords;
   if (report.robots) metadata.robots = report.robots;
   if (report.referrer) metadata.referrer = report.referrer;
+  const sourceOrigin = originOf(report.sourceUrl);
   const alternates: Record<string, unknown> = {};
-  if (report.canonicalUrl) alternates.canonical = report.canonicalUrl;
+  // Canonical is relativized to the source origin path so metadataBase (the clone's own
+  // origin) resolves it — never hard-coding the source domain. Off-origin canonicals are rare;
+  // keep them verbatim.
+  if (report.canonicalUrl) {
+    const c = relativizeToSource(report.canonicalUrl, sourceOrigin);
+    alternates.canonical = c.path;
+  }
   if (report.alternates.length) {
     const languages: Record<string, string> = {};
     for (const alt of report.alternates) languages[alt.hrefLang] = alt.href;
@@ -314,7 +321,7 @@ function metadataObject(report: SeoInventory): Record<string, unknown> {
     else other["og:type"] = ogType;
   }
   if (ogSiteName) og.siteName = ogSiteName;
-  if (ogUrl) og.url = ogUrl;
+  if (ogUrl) og.url = relativizeToSource(ogUrl, sourceOrigin).path;
   if (ogImages.length) og.images = ogImages;
   if (Object.keys(og).length) metadata.openGraph = og;
 
@@ -352,8 +359,23 @@ function metadataObject(report: SeoInventory): Record<string, unknown> {
   return metadata;
 }
 
+// A sentinel object value that metadataExport rewrites into the runtime `metadataBase`
+// expression (JSON can't hold `new URL(...)`). Chosen so it never collides with real content.
+const METADATA_BASE_SENTINEL = "__DITTO_METADATA_BASE__";
+
+// The metadata/JSON-LD layout module references SITE_ORIGIN — callers must hoist this import.
+export const SITE_ORIGIN_LAYOUT_IMPORT = siteOriginImportLine(1);
+
 export function metadataExport(report: SeoInventory): string {
-  return `export const metadata = ${JSON.stringify(metadataObject(report), null, 2)};\n`;
+  const obj = metadataObject(report);
+  // metadataBase lets Next resolve the (now relative) canonical/openGraph URLs against the
+  // clone's OWN origin — SITE_ORIGIN when set, localhost in dev. Placed first for readability.
+  const withBase = { metadataBase: METADATA_BASE_SENTINEL, ...obj };
+  const body = JSON.stringify(withBase, null, 2).replace(
+    JSON.stringify(METADATA_BASE_SENTINEL),
+    `new URL(SITE_ORIGIN || "http://localhost:3000")`,
+  );
+  return `export const metadata = ${body};\n`;
 }
 
 export function viewportExport(report: SeoInventory): string {
@@ -367,13 +389,31 @@ function safeJsonLd(text: string): string {
   return text.replace(/<\/script/gi, "<\\/script").replace(/<!--/g, "<\\!--");
 }
 
+/** Rewrite a JSON-LD block's on-origin @id/url/contentUrl/target values off the SOURCE domain.
+ *  The frozen JSON escapes slashes (`https:\/\/host\/…`), so we split on both the escaped and
+ *  plain origin forms and rejoin with SITE_ORIGIN at RUNTIME — the source domain never appears
+ *  in output, and setting NEXT_PUBLIC_SITE_ORIGIN re-hosts the ids under the clone's own origin.
+ *  Returns a JS expression string. Off-origin links (genuinely external) are left untouched. */
+function jsonLdHtmlExpr(text: string, sourceOrigin: string): string {
+  const safe = safeJsonLd(text);
+  if (!sourceOrigin) return JSON.stringify(safe);
+  const escaped = sourceOrigin.replace(/\//g, "\\/");
+  // Split on whichever origin form appears; only one form is present in a given block.
+  const forms = safe.includes(escaped) ? escaped : (safe.includes(sourceOrigin) ? sourceOrigin : null);
+  if (!forms) return JSON.stringify(safe);
+  const segments = safe.split(forms);
+  if (segments.length === 1) return JSON.stringify(safe);
+  return `[${segments.map((s) => JSON.stringify(s)).join(", ")}].join(SITE_ORIGIN)`;
+}
+
 export function jsonLdHeadMarkup(report: SeoInventory, indent = 8): string {
   if (!report.jsonLd.length) return "";
   const pad = " ".repeat(indent);
+  const sourceOrigin = originOf(report.sourceUrl);
   return report.jsonLd.map((entry, index) => `${pad}<script
 ${pad}  key="ditto-json-ld-${index}"
 ${pad}  type="application/ld+json"
-${pad}  dangerouslySetInnerHTML={{ __html: ${JSON.stringify(safeJsonLd(entry.text))} }}
+${pad}  dangerouslySetInnerHTML={{ __html: ${jsonLdHtmlExpr(entry.text, sourceOrigin)} }}
 ${pad}/>`).join("\n");
 }
 
@@ -397,6 +437,27 @@ function originOf(url: string): string {
   try { return new URL(url).origin; } catch { return "https://example.com"; }
 }
 
+/** The single origin constant every generated SEO/metadata route resolves against. Empty by
+ *  default so canonical/sitemap/JSON-LD URLs render RELATIVE to wherever the clone is served
+ *  (never the source domain); set NEXT_PUBLIC_SITE_ORIGIN to make them absolute to the clone's
+ *  own origin. Emitted once as src/lib/site.ts. */
+export const SITE_ORIGIN_MODULE = `export const SITE_ORIGIN = (process.env.NEXT_PUBLIC_SITE_ORIGIN ?? "").replace(/\\/$/, "");\n`;
+
+/** The `import { SITE_ORIGIN } from "…/lib/site"` line; `depth` mirrors cnImportLine. */
+export function siteOriginImportLine(depth: number): string {
+  return `import { SITE_ORIGIN } from "${"../".repeat(Math.max(1, depth))}lib/site";`;
+}
+
+/** Path portion of a URL that sits on the source origin (so it can be re-hosted under
+ *  SITE_ORIGIN); returns the input unchanged for off-origin (genuinely external) URLs. */
+function relativizeToSource(url: string, sourceOrigin: string): { onOrigin: boolean; path: string } {
+  if (sourceOrigin && url.startsWith(sourceOrigin)) {
+    const path = url.slice(sourceOrigin.length) || "/";
+    return { onOrigin: true, path: path.startsWith("/") ? path : "/" + path };
+  }
+  return { onOrigin: false, path: url };
+}
+
 function generatedLlms(report: SeoInventory, routes: SeoRouteSummary[]): string {
   const title = report.title || routes[0]?.title || "Generated Clone";
   const lines: string[] = [`# ${title}`, ""];
@@ -422,15 +483,17 @@ function generatedLlms(report: SeoInventory, routes: SeoRouteSummary[]): string
 
 export function seoRouteFiles(report: SeoInventory, routes: SeoRouteSummary[]): Array<[string, string]> {
   const origin = originOf(report.sourceUrl);
-  const sitemapUrl = origin + "/sitemap.xml";
+  // robots.ts / sitemap.ts live at src/app → depth 1 below src.
+  const siteImport = siteOriginImportLine(1);
   const robots = `import type { MetadataRoute } from "next";
+${siteImport}
 
 export const dynamic = "force-static";
 
 export default function robots(): MetadataRoute.Robots {
   return {
     rules: { userAgent: "*", allow: "/" },
-    sitemap: ${JSON.stringify(sitemapUrl)},
+    sitemap: SITE_ORIGIN + "/sitemap.xml",
   };
 }
 `;
@@ -441,13 +504,21 @@ export default function robots(): MetadataRoute.Robots {
     title: report.title || "Home",
     description: report.description,
     excerpt: "",
-  }]).map((route, index) => ({ url: route.url, changeFrequency: "weekly", priority: index === 0 ? 1 : 0.7 }));
+  }]).map((route, index) => ({ path: relativizeToSource(route.url, origin).path, changeFrequency: "weekly", priority: index === 0 ? 1 : 0.7 }));
+  // Emit `url: SITE_ORIGIN + "<path>"` so URLs resolve to the clone's own origin (relative by
+  // default), never the source domain.
+  const entryLines = sitemapEntries.map((e) =>
+    `  {\n    url: SITE_ORIGIN + ${JSON.stringify(e.path)},\n    changeFrequency: ${JSON.stringify(e.changeFrequency)},\n    priority: ${e.priority},\n  }`
+  ).join(",\n");
   const sitemap = `import type { MetadataRoute } from "next";
+${siteImport}
 
 export const dynamic = "force-static";
 
 export default function sitemap(): MetadataRoute.Sitemap {
-  return ${JSON.stringify(sitemapEntries, null, 2)};
+  return [
+${entryLines},
+  ];
 }
 `;
   const sourceLlms = resourceText(report, "llms");
@@ -472,11 +543,12 @@ function xmlEscape(value: string): string {
 
 export function seoStaticFiles(report: SeoInventory, routes: SeoRouteSummary[]): Array<[string, string]> {
   const origin = originOf(report.sourceUrl);
-  const sitemapUrl = origin + "/sitemap.xml";
+  // Static output (Vite) has no runtime env: emit the clone's own paths RELATIVE to the source
+  // origin so the source domain is never baked in (the requirement's relative default).
   const robots = [
     "User-agent: *",
     "Allow: /",
-    `Sitemap: ${sitemapUrl}`,
+    "Sitemap: /sitemap.xml",
     "",
   ].join("\n");
   const sitemapRoutes = routes.length ? routes : [{
@@ -492,7 +564,7 @@ export function seoStaticFiles(report: SeoInventory, routes: SeoRouteSummary[]):
     '<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">',
     ...sitemapRoutes.map((route, index) => [
       "  <url>",
-      `    <loc>${xmlEscape(route.url)}</loc>`,
+      `    <loc>${xmlEscape(relativizeToSource(route.url, origin).path)}</loc>`,
       "    <changefreq>weekly</changefreq>",
       `    <priority>${index === 0 ? "1.0" : "0.7"}</priority>`,
       "  </url>",
diff --git a/compiler/src/generate/tailwind.ts b/compiler/src/generate/tailwind.ts
index f96d625..46af588 100644
--- a/compiler/src/generate/tailwind.ts
+++ b/compiler/src/generate/tailwind.ts
@@ -18,6 +18,7 @@
 import type { IR, IRNode } from "../normalize/ir.js";
 import { isTextChild } from "../normalize/ir.js";
 import { collectNodeRules, computeBands, keyframesCss, type NodeRule } from "./css.js";
+import { colorClusterKey } from "../infer/semanticTokens.js";
 import type { InteractionCapture, StyleDelta } from "../capture/interactions.js";
 
 // ---- arbitrary-value escaping ----
@@ -28,6 +29,25 @@ import type { InteractionCapture, StyleDelta } from "../capture/interactions.js"
 function arb(v: string): string {
   return v.replace(/"/g, "'").replace(/_/g, "\\_").replace(/ /g, "_");
 }
+
+/** Round a single simple `<number>px|rem` length, killing frozen sub-pixel noise: snap to an
+ *  integer when the value is within 0.1px of one (measurement/rounding jitter — `204.9994px` was
+ *  meant to be `205px`), otherwise keep at most 1 decimal (`204.797px` → `204.8px`, a genuine
+ *  fraction). `627px` is unchanged. Only touches a lone number+unit token: multi-token values,
+ *  calc()/clamp()/var(), percentages, and unitless numbers pass through untouched, so nothing that
+ *  needs exact sub-pixel precision (borders, transforms — handled on their own branches) is moved. */
+export function snapLen(value: string): string {
+  const m = /^(-?\d*\.?\d+)(px|rem)$/.exec(value.trim());
+  if (!m) return value;
+  const n = parseFloat(m[1]!);
+  const unit = m[2]!;
+  // rem thresholds scale by the 16px root so "within 0.1px" is unit-consistent.
+  const pxPerUnit = unit === "rem" ? 16 : 1;
+  const rounded = Math.abs(n - Math.round(n)) * pxPerUnit < 0.1
+    ? Math.round(n)
+    : Math.round(n * 10) / 10;
+  return `${rounded}${unit}`;
+}
 function arbList(v: string): string {
   return arb(v).replace(/,_/g, ",");
 }
@@ -53,6 +73,7 @@ const KW: Record<string, Record<string, string>> = {
   "font-weight": { "100": "font-thin", "200": "font-extralight", "300": "font-light", "400": "font-normal", "500": "font-medium", "600": "font-semibold", "700": "font-bold", "800": "font-extrabold", "900": "font-black" },
   "text-decoration-line": { underline: "underline", "line-through": "line-through", overline: "overline", none: "no-underline" },
   "white-space": { nowrap: "whitespace-nowrap", normal: "whitespace-normal", pre: "whitespace-pre", "pre-line": "whitespace-pre-line", "pre-wrap": "whitespace-pre-wrap", "break-spaces": "whitespace-break-spaces" },
+  "text-wrap": { wrap: "text-wrap", nowrap: "text-nowrap", balance: "text-balance", pretty: "text-pretty" },
   "overflow-x": { hidden: "overflow-x-hidden", auto: "overflow-x-auto", scroll: "overflow-x-scroll", visible: "overflow-x-visible", clip: "overflow-x-clip" },
   "overflow-y": { hidden: "overflow-y-hidden", auto: "overflow-y-auto", scroll: "overflow-y-scroll", visible: "overflow-y-visible", clip: "overflow-y-clip" },
   "object-fit": { contain: "object-contain", cover: "object-cover", fill: "object-fill", none: "object-none", "scale-down": "object-scale-down" },
@@ -243,7 +264,14 @@ export function declToUtil(prop: string, value: string): string {
     if (value === "0" || value === "0px" || value === "0rem") {
       return ZERO_NAMED.has(prop) ? `${ARB[prop]}-0` : `${ARB[prop]}-[0px]`;
     }
-    return `${ARB[prop]}-[${arb(value)}]`;
+    // `snapLen`'s 0.1px integer snap is calibrated for BOX lengths (killing measurement jitter like
+    // `204.9994px`→`205px`). letter-spacing is authored at a far finer scale — a real `-0.08px`/
+    // `-0.0375px` tracking is WITHIN 0.1px of zero, so snapLen would collapse it to `0px`. Chromium
+    // then serializes computed `letter-spacing:0` as the keyword `normal`, which the style gate's
+    // numeric compare can't parse → a false exact-string mismatch. Skip the integer snap for tracking;
+    // `snapBase` rounds it to 2 decimals (`tracking-[-0.08px]`), the right precision for this axis.
+    if (prop === "letter-spacing") return `${ARB[prop]}-[${arb(value)}]`;
+    return `${ARB[prop]}-[${arb(snapLen(value))}]`;
   }
   if (/^border-(top|right|bottom|left)-width$/.test(prop)) {
     const side = prop.split("-")[1]![0]!; // t/r/b/l
@@ -353,7 +381,7 @@ function parseSide(b: string): SidePart | null {
   for (const h of COLLAPSE_HEADS) if (body.startsWith(h + "-")) return { neg, head: h, suf: body.slice(h.length + 1) };
   return null;
 }
-function collapseBases(bases: string[]): string[] {
+export function collapseBases(bases: string[]): string[] {
   const byHead = new Map<string, SidePart>(); // head → its parsed part (sides are unique within a group)
   for (const b of bases) { const p = parseSide(b); if (p) byHead.set(p.head, p); }
   const origOf = new Map<string, string>(); // head → original base string (to drop/replace by identity)
@@ -410,6 +438,18 @@ function collapseBases(bases: string[]): string[] {
   if (wv !== null) { const sfx = wv ? `-${wv}` : ""; replace.set(`border-t${sfx}`, `border${sfx}`); for (const s of ["r", "b", "l"]) drop.add(`border-${s}${sfx}`); }
   const cv = allEqSide(bcSuf);
   if (cv !== null) { replace.set(`border-t-${cv}`, `border-${cv}`); for (const s of ["r", "b", "l"]) drop.add(`border-${s}-${cv}`); }
+  // flex:1 1 0% → the idiomatic `flex-1` (Tailwind `flex-1` compiles to `flex: 1 1 0%`, EXACTLY these
+  // longhands). Fold when this band sets flex-grow:1 (`grow-[1]`) AND a zero flex-basis (`basis-[0%]`,
+  // or its already-shortened `basis-0` — reached from a band delta). flex-shrink is the CSS default 1
+  // (elided) unless an explicit `shrink-0` is present, which would break the equivalence — so require
+  // its absence. Emitting `flex-1` rather than `grow basis-[0%]` also sidesteps the `basis-[0%]`→`basis
+  // -0` prettify hazard (0% content-sizes against an indefinite main axis; 0px is a definite zero).
+  const hasGrow1 = bases.includes("grow-[1]");
+  const zeroBasis = bases.includes("basis-[0%]") ? "basis-[0%]" : bases.includes("basis-0") ? "basis-0" : null;
+  if (hasGrow1 && zeroBasis && !bases.includes("shrink-0")) {
+    replace.set("grow-[1]", "flex-1");
+    drop.add(zeroBasis);
+  }
   const out: string[] = [];
   for (const b of bases) { if (drop.has(b)) continue; out.push(replace.get(b) ?? b); }
   return out;
@@ -490,6 +530,14 @@ export function prettifyBase(base: string): string {
   const pm = /^(w|h|min-w|min-h|basis|inset|inset-x|inset-y|top|right|bottom|left)-\[(\d*\.?\d+)%\]$/.exec(base);
   if (pm) {
     const v = parseFloat(pm[2]!);
+    // A percentage on a MAIN-SIZE axis whose containing block may be indefinite is NOT equal to the
+    // same length in px. `flex-basis:0%` against an auto-sized (indefinite) flex container falls back
+    // to CONTENT sizing per the flexbox spec, whereas `flex-basis:0` (definite zero) gives a zero base
+    // size — collapsing a `flex:1 1 0%` item to 0 in an auto-height column. `height`/`min-height` in %
+    // resolve to `auto` when the containing block's height is indefinite, the same hazard. So never
+    // rewrite `[0%]` to the definite `-0` for these prefixes; keep the literal `basis-[0%]`/`h-[0%]`.
+    // (Width/inset percentages resolve against the always-definite containing-block WIDTH — safe.)
+    if (v === 0 && (pm[1] === "basis" || pm[1] === "h" || pm[1] === "min-h")) return base;
     const frac = FRACTIONS.find(([p]) => Math.abs(p - v) < 0.4);
     return frac ? `${pm[1]}-${frac[1]}` : base;
   }
@@ -544,7 +592,6 @@ function namedText(base: string): string | null {
 // nearest scale step / integer px when comfortably INSIDE that budget (ε well under the gate tol), so
 // the markup reads hand-authored. Bounded ε + the layout & perceptual gates backstop any accumulation;
 // values not near a step stay arbitrary because they are genuine one-offs.
-const SNAP_SPACE_PX = 1.0; // padding/margin/gap/inset/size → nearest 0.25rem scale step within this
 const SNAP_TYPE_PX = 0.6;  // font-size/line-height/radius → nearest integer px within this
 const NAMED_K_SORTED = [...NAMED_K].sort((a, b) => a - b);
 function nearestNamedK(k: number): number {
@@ -552,7 +599,7 @@ function nearestNamedK(k: number): number {
   for (const c of NAMED_K_SORTED) if (Math.abs(c - k) < Math.abs(best - k)) best = c;
   return best;
 }
-function snapBase(base: string): string {
+export function snapBase(base: string): string {
   const m = /^(-?)([a-z][a-z-]*)-\[(-?\d*\.?\d+)(px|rem)\]$/.exec(base);
   if (!m) return base;
   const neg = m[1]!, prefix = m[2]!, px = parseFloat(m[3]!) * (m[4] === "rem" ? 16 : 1);
@@ -568,10 +615,16 @@ function snapBase(base: string): string {
     if (Math.abs(r - px) <= SNAP_TYPE_PX && r in RADIUS_SUFFIX) return `${prefix}${RADIUS_SUFFIX[r]}`;
     return base;
   }
-  // spacing / size → nearest named scale step (0.25rem grid)
+  // spacing / size → nearest named scale step (0.25rem grid). Only snap a value that lands ESSENTIALLY
+  // ON a step (≤0.25px): the scale is 2px-granular (`p-0.5`=2px, `p-1.5`=6px), so a captured value ≥0.25px
+  // off the nearest step is a genuine sub-step measurement (3.5px is BETWEEN 2px and 4px — not on the
+  // scale). Snapping such a value up by +0.5px per side accumulates across the links of a fixed-width
+  // flex row until the items overflow and wrap to a second line; the exact `p-[3.5px]` cannot. The wider
+  // ±1px budget the gate tolerates in isolation is unsafe here because the error is systematic, not
+  // random. Values genuinely on a step (2px→`p-0.5`, 4px→`p-1`) still snap.
   if (SCALE_PREFIXES.has(prefix)) {
     const k = nearestNamedK(px / 4);
-    if (Math.abs(k * 4 - px) <= SNAP_SPACE_PX) return k === 0 ? `${neg}${prefix}-0` : `${neg}${prefix}-${k}`;
+    if (Math.abs(k * 4 - px) <= 0.25) return k === 0 ? `${neg}${prefix}-0` : `${neg}${prefix}-${k}`;
   }
   return base;
 }
@@ -694,6 +747,25 @@ function sourceVariantActive(variant: string, vp: number): boolean {
   return true;
 }
 
+// Tailwind cascade specificity of an ACTIVE variant at a viewport: the effective min-width its media
+// query opens at, so a more-specific (higher) breakpoint wins over a lower one. Tailwind emits its
+// utilities sorted by breakpoint (min-width ascending), NOT by class-attribute order, so when both
+// `md:` and `lg:` apply at 1280 the `lg:` rule wins regardless of which appears first in the class
+// string. `min-[Npx]:` embeds N; a bare min breakpoint uses its threshold; `max-*` variants are
+// upper-bounded windows that a plain min variant out-specifies, so they score below any min. The
+// unprefixed base scores 0. Only meaningful for variants already known active at `vp`.
+function sourceVariantSpecificity(variant: string, vp: number): number {
+  if (!variant) return 0;
+  let score = 0;
+  for (const part of variant.split(":").filter(Boolean)) {
+    const minArb = /^min-\[(\d+)px\]$/.exec(part);
+    if (minArb) { score = Math.max(score, +minArb[1]!); continue; }
+    if (part in SOURCE_BP) { score = Math.max(score, SOURCE_BP[part]!); continue; }
+    // max-* windows are less specific than any min breakpoint; leave score as-is (a min wins).
+  }
+  return score;
+}
+
 function sourceArbitraryInner(suffix: string): string | null {
   return suffix.startsWith("[") && suffix.endsWith("]") ? suffix.slice(1, -1) : null;
 }
@@ -709,6 +781,118 @@ function sourceFluidLengthSuffix(suffix: string): boolean {
   return /(%|vw|vh|svw|lvw|dvw|svh|lvh|dvh|fr|min-content|max-content|fit-content)/.test(inner);
 }
 
+// A FIXED, definite authored length suffix on a `w-`/`h-` utility: an arbitrary `[<px|rem|em|…>]`, the
+// `px` token (1px), or a numeric spacing-scale token (`24`, `2.5` → fixed rem). Unlike
+// sourceFluidLengthSuffix these do NOT re-derive from the container, so the source-intent pass must
+// re-emit them as the CAPTURED computed px (the clone's root font-size may differ from the source's, so
+// echoing `h-[4rem]` verbatim would mis-size), and only where geometry corroborates the resolved box.
+function sourceFixedLengthSuffix(suffix: string): boolean {
+  const inner = sourceArbitraryInner(suffix);
+  if (inner !== null) {
+    const v = inner.trim().toLowerCase();
+    if (/^var\(/.test(v)) return false;                                  // handled by the var-length path
+    if (/%|vw|vh|vmin|vmax|svw|lvw|dvw|svh|lvh|dvh|\bfr\b|min-content|max-content|fit-content/.test(v)) return false;
+    return /(?:^|[\s(*/+-])[\d.]+(?:px|rem|em|cm|mm|in|pt|pc|ex|ch|q)\b/.test(v);
+  }
+  if (suffix === "px") return true;
+  return /^\d+(?:\.\d+)?$/.test(suffix);
+}
+
+// A `w-`/`h-` utility carrying a fixed authored length (as recognised by sourceFixedLengthSuffix).
+function isFixedLengthUtil(util: string): boolean {
+  const m = /^([wh])-(.+)$/.exec(util);
+  return !!m && sourceFixedLengthSuffix(m[2]!);
+}
+
+// The captured computed px on this axis is definite and matches the measured bbox — i.e. the authored
+// fixed length resolved to the box the capture recorded. Geometry corroboration for a fixed w/h util.
+function fixedLengthResolvesToBox(node: IRNode, axis: "w" | "h", vp: number): boolean {
+  const cs = node.computedByVp[vp]; const b = node.bboxByVp[vp];
+  if (!cs || !b) return false;
+  const val = axis === "h" ? cs.height : cs.width;
+  const ext = axis === "h" ? b.height : b.width;
+  if (!val || val === "auto" || !/px$/.test(val)) return false;
+  if (!(ext > 0)) return false;
+  return Math.abs(pf(val) - ext) <= Math.max(1.5, 0.01 * ext);
+}
+
+// Rewrite a fixed-length `w-`/`h-` source utility to the node's CAPTURED computed px at a viewport,
+// preserving any variant prefix. `h-[4rem]` → `h-[60px]` (the source resolved 4rem against a 15px root;
+// the clone's root may differ, so bake the measured px). Returns the utility unchanged when it is not a
+// fixed-length util or the computed px is unavailable.
+function fixedLengthUtilAsPx(util: string, node: IRNode, vp: number): string {
+  const m = VARIANT_PREFIX.exec(util);
+  const prefix = m ? m[1]! : "";
+  const core = m ? m[2]! : util;
+  const sm = /^([wh])-(.+)$/.exec(core);
+  if (!sm || !sourceFixedLengthSuffix(sm[2]!)) return util;
+  const val = sm[1] === "h" ? node.computedByVp[vp]?.height : node.computedByVp[vp]?.width;
+  if (!val || !/px$/.test(val)) return util;
+  const px = Math.round(pf(val) * 100) / 100;
+  return `${prefix}${sm[1]}-[${px}px]`;
+}
+
+// Tailwind v4's `max-w-*` / `w-*` / `h-*` / `max-h-*` NAMED size scale (the `--container-*` theme
+// values), in px at a 16px root. A source built on an OLDER Tailwind authored these names against a
+// DIFFERENT scale (e.g. v0–v2 `max-w-md` = 640px vs v4's 448px), so re-emitting the name verbatim
+// silently re-sizes the box. The source-intent pass validates the modern px below and falls back to
+// the captured computed px when they disagree.
+const CONTAINER_NAMED_PX: Record<string, number> = {
+  "3xs": 256, "2xs": 288, xs: 320, sm: 384, md: 448, lg: 512, xl: 576,
+  "2xl": 672, "3xl": 768, "4xl": 896, "5xl": 1024, "6xl": 1152, "7xl": 1280,
+};
+
+// The px a `w-`/`h-`/`max-w-`/`max-h-` NAMED or numeric-scale suffix resolves to under THIS clone's
+// Tailwind v4 (16px root). Covers the `--container-*` names (`md`→448) and the numeric spacing scale
+// (`24`→96px, `2.5`→10px). Returns null for relative/keyword/arbitrary suffixes (`full`, `1/2`,
+// `screen`, `[…]`, `prose`) — those re-derive from context and are not px-fixed, so they need no
+// value validation and are re-emitted verbatim.
+function namedLengthPx(suffix: string): number | null {
+  if (suffix in CONTAINER_NAMED_PX) return CONTAINER_NAMED_PX[suffix]!;
+  if (suffix === "px") return 1;
+  if (/^\d+(?:\.\d+)?$/.test(suffix)) return parseFloat(suffix) * 4; // spacing scale: n × 0.25rem
+  return null;
+}
+
+// A source utility on a length axis whose suffix is a NAMED/numeric-scale token (px-fixed under
+// v4) rather than a relative/keyword/arbitrary one. Only these need modern-value validation; e.g.
+// `max-w-md`, `w-24`, `h-px` — but not `max-w-full`, `w-1/2`, `h-[4rem]`.
+function namedScaleCore(core: string): { axis: "w" | "h" | "max-w" | "max-h"; px: number } | null {
+  const m = /^(max-w|max-h|w|h)-(.+)$/.exec(core);
+  if (!m) return null;
+  const px = namedLengthPx(m[2]!);
+  return px === null ? null : { axis: m[1] as "w" | "h" | "max-w" | "max-h", px };
+}
+
+// Captured computed px on the axis at a viewport, when definite (`…px`, not `auto`/`none`). The
+// property a length axis constrains: `max-width` / `max-height` / `width` / `height`.
+function computedAxisPx(node: IRNode, axis: SourceAxis, vp: number): number | null {
+  const cs = node.computedByVp[vp];
+  if (!cs) return null;
+  const raw = axis === "max-w" ? cs.maxWidth : axis === "max-h" ? cs.maxHeight
+    : axis === "w" ? cs.width : axis === "h" ? cs.height : undefined;
+  if (!raw || raw === "auto" || raw === "none" || !/px$/.test(raw)) return null;
+  return pf(raw);
+}
+
+// Re-emit a source length utility for one viewport. When the suffix is a NAMED/numeric-scale token
+// (px-fixed under v4) and its modern px does NOT match the captured computed px (within tolerance),
+// the authored name meant a different length on the source's older Tailwind — emit the captured px
+// as an arbitrary value instead of the mis-resolving name. Fluid/keyword/fixed-arbitrary suffixes
+// (and the already-handled fixed w/h path) pass through unchanged.
+function namedLengthUtilChecked(util: string, node: IRNode, axis: SourceAxis, vp: number): string {
+  const m = VARIANT_PREFIX.exec(util);
+  const prefix = m ? m[1]! : "";
+  const core = m ? m[2]! : util;
+  const named = namedScaleCore(core);
+  if (!named) return util;
+  const computed = computedAxisPx(node, axis, vp);
+  if (computed === null) return util; // no definite computed px to check against — keep authored name
+  if (Math.abs(named.px - computed) <= Math.max(1.5, 0.02 * computed)) return util; // modern value agrees
+  const rem = pxToRem(computed);
+  return `${prefix}${named.axis}-[${rem ?? computed + "px"}]`;
+}
+
 function sourceAspectUtility(core: string): string | null {
   let m = /^aspect-(\d+)\/(\d+)-box$/.exec(core);
   if (m) return m[1] === m[2] ? "aspect-square" : `aspect-[${m[1]}/${m[2]}]`;
@@ -740,7 +924,7 @@ function sourceAxisForCore(core0: string): { axis: SourceAxis; utility: string }
   const maxH = /^max-h-(.+)$/.exec(core);
   if (maxH && sourceFluidLengthSuffix(maxH[1]!)) return { axis: "max-h", utility: core };
   const size = /^([wh])-(.+)$/.exec(core);
-  if (size && sourceFluidLengthSuffix(size[2]!)) return { axis: size[1] as SourceAxis, utility: core };
+  if (size && (sourceFluidLengthSuffix(size[2]!) || sourceFixedLengthSuffix(size[2]!))) return { axis: size[1] as SourceAxis, utility: core };
   return null;
 }
 
@@ -904,6 +1088,12 @@ function sourceAxisCompatible(node: IRNode, parent: IRNode | undefined, axis: So
       if (axis === "h" && v === "h-full") return !!s?.hFill;
       if (axis === "h" && v === "h-auto") return !!s?.hAuto;
       if (axis === "h" && v && sourceVarName(v)) return /px$/.test(node.computedByVp[vp]?.height || "");
+      // A FIXED authored length (`h-[4rem]`, `w-24`, `h-px`) — the source-intent pass will re-emit it as
+      // the captured computed px. Compatible when that px is definite and equals the measured bbox extent
+      // at this viewport (the authored length actually resolved to the captured box). This recovers a
+      // banded authored fixed height/width the sizing probe dropped through the fill↔content cycle
+      // (h-full) or the content/fill drop (auto), without depending on the clone's root font-size.
+      if (v && isFixedLengthUtil(v)) return fixedLengthResolvesToBox(node, axis, vp);
       return false;
     });
   }
@@ -932,6 +1122,13 @@ function sourceIntentVarCss(node: IRNode, axis: SourceAxis, values: Map<number,
 
 function sourceIntentUtilities(node: IRNode, parent: IRNode | undefined, viewports: number[], canonical: number): SourceIntent {
   const perAxis = new Map<SourceAxis, Map<number, string>>();
+  // Per (axis, vp): the cascade specificity of the currently-chosen active token, so a later token in
+  // the class string can only override an earlier one when it is at least as specific. Tailwind sorts
+  // its emitted rules by breakpoint (min-width), so when both `md:` and `lg:` apply at a wide viewport
+  // the `lg:` value wins — regardless of the class-attribute order. Picking the LAST active token
+  // instead (class-string order) silently takes `md:grid-cols-2` at 1280 for `lg:grid-cols-3
+  // md:grid-cols-2`, dropping the desktop column count.
+  const specAt = new Map<SourceAxis, Map<number, number>>();
   for (const tok of parseSourceClass(node.srcClass)) {
     const parsed = sourceAxisForCore(tok.core);
     if (!parsed) continue;
@@ -939,7 +1136,12 @@ function sourceIntentUtilities(node: IRNode, parent: IRNode | undefined, viewpor
       if (!sourceVariantActive(tok.variant, vp)) continue;
       let m = perAxis.get(parsed.axis);
       if (!m) { m = new Map<number, string>(); perAxis.set(parsed.axis, m); }
-      m.set(vp, parsed.utility);
+      let s = specAt.get(parsed.axis);
+      if (!s) { s = new Map<number, number>(); specAt.set(parsed.axis, s); }
+      const spec = sourceVariantSpecificity(tok.variant, vp);
+      // `>=` so a later token at EQUAL specificity still wins (matches source order for same-breakpoint
+      // duplicates), but a lower breakpoint can never displace a higher one already chosen.
+      if (!m.has(vp) || spec >= (s.get(vp) ?? -1)) { m.set(vp, parsed.utility); s.set(vp, spec); }
     }
   }
   const axes = new Set<SourceAxis>();
@@ -947,15 +1149,47 @@ function sourceIntentUtilities(node: IRNode, parent: IRNode | undefined, viewpor
   const css: string[] = [];
   const bands = computeBands(viewports, canonical);
   for (const [axis, byVp] of perAxis) {
-    if (!viewports.every((vp) => byVp.has(vp))) continue; // avoid partial custom-class inference for now
+    if (!viewports.every((vp) => byVp.has(vp))) {
+      // Partial-coverage escape hatch for SUBGRID. `grid-rows-subgrid`/`grid-cols-subgrid` is a
+      // structural keyword authored as a variant-only utility (`max-lg:grid-rows-subgrid`, with the
+      // axis resolving to explicit tracks at ≥lg), so the map covers only a subset of viewports and
+      // the full-coverage bail below would throw it away. Subgrid is safe to band partially: emit it
+      // exactly at the covered viewports as banded variants (and as the base only when canonical is
+      // covered). Adding the axis lets the redundant computed-derived subgrid bands drop in favour of
+      // this authored intent. Other partial axes still bail (partial fluid inference is unsafe).
+      const subgridOnly = (axis === "grid-rows" || axis === "grid-cols") &&
+        [...byVp.values()].every((u) => /-subgrid$/.test(u));
+      if (!subgridOnly) continue;
+      if (!sourceAxisCompatible(node, parent, axis, byVp, viewports)) continue;
+      axes.add(axis);
+      const canon = byVp.get(canonical);
+      if (canon) utilities.push(canon);
+      for (const b of bands) {
+        if (!b.media) continue;
+        const v = byVp.get(b.vp);
+        if (v && v !== canon) utilities.push(prefixFor(b.media) + v);
+      }
+      continue;
+    }
     if (!sourceAxisCompatible(node, parent, axis, byVp, viewports)) continue;
-    const base = byVp.get(canonical)!;
+    // A fixed-length w/h axis re-emits the CAPTURED computed px per band (root-font-size independent),
+    // not the source rem token. A NAMED/numeric-scale length token (`max-w-md`, `w-24`) is re-emitted
+    // only when its modern Tailwind-v4 px matches the captured computed px; otherwise the authored
+    // name meant a different length on the source's older Tailwind and the captured px is emitted as an
+    // arbitrary value. Every other axis keeps its authored utility verbatim.
+    const asEmit = (vp: number): string => {
+      const u = byVp.get(vp)!;
+      if ((axis === "w" || axis === "h") && isFixedLengthUtil(u)) return fixedLengthUtilAsPx(u, node, vp);
+      if (axis === "w" || axis === "h" || axis === "max-w" || axis === "max-h") return namedLengthUtilChecked(u, node, axis, vp);
+      return u;
+    };
+    const base = asEmit(canonical);
     axes.add(axis);
     if (axis === "aspect") axes.add("grid-rows");
     utilities.push(base);
     for (const b of bands) {
       if (!b.media) continue;
-      const v = byVp.get(b.vp)!;
+      const v = asEmit(b.vp);
       if (v !== base) utilities.push(prefixFor(b.media) + v);
     }
     css.push(...sourceIntentVarCss(node, axis, byVp, viewports, canonical));
@@ -988,11 +1222,12 @@ export type TailwindOutput = {
 export type ColorInterner = {
   defs: Map<string, string>;    // minted token name → literal value
   byValue: Map<string, string>; // literal value → minted token name
+  byKey: Map<string, string>;   // rounded-sRGB cluster key → minted token name (visual dedup)
   tokens: Set<string>;          // ALL referenced color token names (palette + minted)
   seq: { n: number };           // monotonic counter for clr-N names
 };
 export function createColorInterner(): ColorInterner {
-  return { defs: new Map(), byValue: new Map(), tokens: new Set(), seq: { n: 0 } };
+  return { defs: new Map(), byValue: new Map(), byKey: new Map(), tokens: new Set(), seq: { n: 0 } };
 }
 /** `:root { --clr-N: <literal>; … }` for the interner's minted tokens (empty if none). */
 export function colorDefsCssOf(it: ColorInterner): string {
@@ -1053,11 +1288,11 @@ function interactionUtilities(
   return { byCid, groups };
 }
 
-export function buildTailwind(ir: IR, assetMap: Map<string, string>, colorVar?: (v: string) => string | null, opts?: { interner?: ColorInterner; includeNode?: (id: string) => boolean; interaction?: InteractionCapture; reflow?: boolean }): TailwindOutput {
+export function buildTailwind(ir: IR, assetMap: Map<string, string>, colorVar?: (v: string) => string | null, opts?: { interner?: ColorInterner; includeNode?: (id: string) => boolean; interaction?: InteractionCapture; reflow?: boolean; lottieMounts?: ReadonlySet<string> }): TailwindOutput {
   // Colors tokenized (var(--…)); typography/geometry kept RAW (text-[16px] reads cleaner
   // than a token ref). The full tokenResolver is deliberately NOT passed — only colors are
   // tokenized below, so spacing/type stay as readable arbitrary values.
-  const rules = collectNodeRules(ir, assetMap, opts?.includeNode, colorVar, undefined, opts?.reflow);
+  const rules = collectNodeRules(ir, assetMap, opts?.includeNode, colorVar, undefined, opts?.reflow, opts?.lottieMounts);
   const classOf = new Map<string, string>();
   const styleOf = new Map<string, Map<string, string>>(); // cid → inline style (base-only gradients/url)
   const extraParts: string[] = []; // pseudo rules + url()-bearing decls, keyed by [data-cid]
@@ -1075,12 +1310,31 @@ export function buildTailwind(ir: IR, assetMap: Map<string, string>, colorVar?:
   indexNode(ir.root);
 
   // Color interner: every distinct color value → a stable theme token referenced as
-  // var(--…). Palette colors already arrive as var(--color-*) (kept, semantic); any other
-  // color is minted a numbered token (--clr-N) so raw rgb/hex NEVER lands in markup.
-  // The token holds the literal value, minted in deterministic first-encounter order.
+  // var(--…). A color the semantic palette recognizes (exactly OR within the grader's ±2
+  // sRGB tolerance — the same tolerance css.ts already trusts for color/bg/border) reuses
+  // that SEMANTIC name (--primary, --surface, --color-001…), so oklab/lch colours reached
+  // only through decoration/gradient/shadow props no longer each mint a fresh opaque
+  // --clr-N. Only colours with NO palette role fall through to a numbered --clr-N token,
+  // minted in deterministic first-encounter order (the literal is kept, byte-exact).
   const internColor = (literal: string): string => {
+    const semantic = colorVar?.(literal);
+    if (semantic) { const n = tokenName(semantic); if (n) colorTokens.add(n); return semantic; }
     let name = interner.byValue.get(literal);
-    if (!name) { name = `clr-${interner.seq.n++}`; interner.byValue.set(literal, name); interner.defs.set(name, literal); }
+    if (!name) {
+      // Dedup visually-identical literals (many oklab()/lch() forms round to the same sRGB):
+      // reuse the token minted for that colour rather than a fresh --clr-N. Fidelity-neutral —
+      // the grader compares in sRGB and the shared token holds the FIRST literal (within ±0 of
+      // its own colour). Values that don't parse fall back to exact-literal keying.
+      const key = colorClusterKey(literal);
+      const existing = key ? interner.byKey.get(key) : undefined;
+      if (existing) { name = existing; interner.byValue.set(literal, name); }
+      else {
+        name = `clr-${interner.seq.n++}`;
+        interner.byValue.set(literal, name);
+        interner.defs.set(name, literal);
+        if (key) interner.byKey.set(key, name);
+      }
+    }
     colorTokens.add(name);
     return `var(--${name})`;
   };
@@ -1131,7 +1385,11 @@ export function buildTailwind(ir: IR, assetMap: Map<string, string>, colorVar?:
     // one-off — emit it as an inline `style={{…}}` (exact, no Tailwind-escape mangling) so the node
     // needs no `[data-cid]` ditto.css rule and the shipped data-cid is stripped. If the prop IS
     // banded, it must stay in ditto.css: an inline style would out-specify the @media override.
-    const bandedRawProps = new Set<string>(bandRaws.flatMap((b) => [...b.raw.keys()]));
+    // Count EVERY band-touched prop (raw or not), not just the raw ones: a band that RESETS the prop
+    // to a non-raw value (e.g. `max-lg:bg-[none]` turning a gradient off on mobile) becomes a utility
+    // rather than a raw decl, so a raw-only set misses it — and inlining the base gradient then
+    // out-specifies the `@media` reset, painting the gradient where the source turned it off.
+    const bandedRawProps = new Set<string>(nr.bands.flatMap((b) => [...b.decls.keys()]));
     const inlineStyle = new Map<string, string>();
     for (const [p, v] of [...baseRaw]) {
       if (!bandedRawProps.has(p)) { inlineStyle.set(p, tokenizeColors(p, v)); baseRaw.delete(p); }
@@ -1222,7 +1480,7 @@ export function buildTailwind(ir: IR, assetMap: Map<string, string>, colorVar?:
  *  + breakpoint bindings, our token :root, and our reset/fonts/page-base inside @layer base
  *  so utilities override them. */
 export function tailwindGlobalsCss(opts: {
-  reset: string; fontCss: string; tokensCss: string; htmlBg: string; bodyFont: string;
+  reset: string; fontCss: string; tokensCss: string; htmlBg: string | null; bodyFont: string;
   clip: string; colorTokens: string[]; viewports: number[]; canonical: number;
 }): string {
   const screens = [
@@ -1250,8 +1508,7 @@ ${opts.tokensCss}
 ${opts.reset}
 /* fonts */
 ${opts.fontCss}
-html { background: ${opts.htmlBg}; }
-body { font-family: ${opts.bodyFont}; }${opts.clip}
+${opts.htmlBg !== null ? `html { background: ${opts.htmlBg}; }\n` : ""}body { font-family: ${opts.bodyFont}; }${opts.clip}
 }
 `;
 }
diff --git a/compiler/src/infer/fonts.ts b/compiler/src/infer/fonts.ts
index 0271864..c2cfeb6 100644
--- a/compiler/src/infer/fonts.ts
+++ b/compiler/src/infer/fonts.ts
@@ -61,19 +61,14 @@ export function buildFontGraph(fontFaces: FontFace[], assetGraph: AssetGraph, so
     }
   }
 
-  const entries: FontEntry[] = [];
-  const cssBlocks: string[] = [];
-  const seen = new Set<string>();
-
-  for (const ff of fontFaces) {
-    const weight = (ff.weight || "400").trim();
-    const style = (ff.style || "normal").trim();
-    const display = (ff.display || "swap").trim();
-    const key = `${ff.family}|${weight}|${style}|${ff.unicodeRange ?? ""}`;
-    if (seen.has(key)) continue;
-    seen.add(key);
-
-    const srcs = parseSrcUrls(ff.src, sourceUrl);
+  // Resolve one face's src descriptor against the downloaded-asset graph. A face harvested from
+  // CSSOM carries the url of its owning sheet in `baseHref`; its relative src url()s must resolve
+  // against THAT, not the document, or `../media/x` clamps to the wrong path (commonly the SPA
+  // router's HTML shell). Faces parsed out-of-band already have absolute srcs baked in, so
+  // `baseHref` is absent and the document url is a harmless fallback.
+  const order = ["woff2", "woff", "truetype", "opentype", "embedded-opentype"];
+  const resolveFace = (ff: FontFace): { resolved: Array<{ localPath: string; format: string }>; dataUris: string[] } => {
+    const srcs = parseSrcUrls(ff.src, ff.baseHref || sourceUrl);
     const resolved: Array<{ localPath: string; format: string }> = [];
     const dataUris: string[] = [];
     for (const s of srcs) {
@@ -84,10 +79,47 @@ export function buildFontGraph(fontFaces: FontFace[], assetGraph: AssetGraph, so
         resolved.push({ localPath: entry.localPath, format: s.format || FORMAT_BY_EXT[ext] || "woff2" });
       }
     }
-
     // Prefer woff2 > woff > others for ordering.
-    const order = ["woff2", "woff", "truetype", "opentype", "embedded-opentype"];
     resolved.sort((a, b) => order.indexOf(a.format) - order.indexOf(b.format));
+    return { resolved, dataUris };
+  };
+
+  // Deduplicate faces by family|weight|style|unicodeRange. Two sources can supply the same face
+  // with DIFFERENT (correctly- vs wrongly-resolved) src urls — the CSSOM harvest and the css-text
+  // parse both land in `fontFaces`. Keeping the first-inserted face lets a src that resolves to
+  // nothing (a rejected impostor, or a mis-based path) win the slot, so choose validity-aware:
+  // the first face whose src resolves to a downloaded/data-uri source wins; only if NONE in the
+  // group resolves do we fall back to the first-seen face (recorded as unavailable). Ties (more
+  // than one resolving) keep insertion order — determinism preserved.
+  const chosen = new Map<string, { ff: FontFace; res: ReturnType<typeof resolveFace> }>();
+  const orderKeys: string[] = [];
+  for (const ff of fontFaces) {
+    const weight = (ff.weight || "400").trim();
+    const style = (ff.style || "normal").trim();
+    const key = `${ff.family}|${weight}|${style}|${ff.unicodeRange ?? ""}`;
+    const res = resolveFace(ff);
+    const resolves = res.resolved.length > 0 || res.dataUris.length > 0;
+    const prev = chosen.get(key);
+    if (!prev) {
+      chosen.set(key, { ff, res });
+      orderKeys.push(key);
+    } else if (resolves && !(prev.res.resolved.length > 0 || prev.res.dataUris.length > 0)) {
+      // Upgrade: the incumbent resolved to nothing, this candidate resolves — replace it in place
+      // (keeping its original emission position).
+      chosen.set(key, { ff, res });
+    }
+    // Otherwise keep the incumbent (first-resolving wins; ties hold insertion order).
+  }
+
+  const entries: FontEntry[] = [];
+  const cssBlocks: string[] = [];
+
+  for (const key of orderKeys) {
+    const { ff, res } = chosen.get(key)!;
+    const weight = (ff.weight || "400").trim();
+    const style = (ff.style || "normal").trim();
+    const display = (ff.display || "swap").trim();
+    const { resolved, dataUris } = res;
 
     if (resolved.length > 0 || dataUris.length > 0) {
       const srcParts: string[] = [];
diff --git a/compiler/src/infer/sections.ts b/compiler/src/infer/sections.ts
index be70454..03f707f 100644
--- a/compiler/src/infer/sections.ts
+++ b/compiler/src/infer/sections.ts
@@ -4,10 +4,19 @@ import { round } from "../util/canonical.js";
 
 /**
  * Deterministic section detection. Splits the page into visually coherent
- * top-level blocks using semantic tags and geometry (we do not rely on class
- * names — those are intentionally dropped from the IR). Sections are metadata:
- * stable ids + per-viewport bboxes for the layout/section gate. Role guesses are
- * advisory and never affect fidelity.
+ * top-level bands using semantic tags and geometry (we do not rely on class
+ * names — those are intentionally dropped from the IR).
+ *
+ * The core is a recursive descent: a container that covers most of the page
+ * (<body> → <div id=root> → <main>) is a WRAPPER, not a band — descend into it
+ * and re-collect among its children, repeating until every candidate is
+ * band-like. A descent only replaces the container when its children actually
+ * tile it (stacked full-width blocks with near-complete coverage), so a page
+ * that truly is one tall band legally stays a single section.
+ *
+ * Sections are metadata: stable ids + per-viewport bboxes for the layout/section
+ * gate, and the shared root set for section-per-file emission (sectionSplit).
+ * Role guesses are advisory and never affect fidelity.
  */
 
 export type Section = {
@@ -19,104 +28,162 @@ export type Section = {
 };
 
 const SEMANTIC = new Set(["header", "nav", "main", "section", "article", "footer", "aside"]);
+const MIN_BAND_H = 64;
+const MIN_SEMANTIC_H = 24; // a 62px navbar is still the navbar
+const MIN_BAND_W_FRAC = 0.55; // a band spans most of the viewport
+const WRAPPER_FRAC = 0.5; // taller than this fraction of the page → wrapper, try descending
+const MIN_CHILD_COVERAGE = 0.8; // children must tile the container to replace it
+const MAX_STACK_OVERLAP = 0.3; // consecutive bands may overlap at most this much of the smaller
+const MAX_BANDS_PER_SPLIT = 20; // a split into more pieces than this is fragmentation, not bands
+const MAX_DEPTH = 12;
 
-type Cand = { node: IRNode; path: string; y: number; width: number; height: number };
+type Cand = { node: IRNode; y: number; width: number; height: number };
+type Ctx = { cw: number; pageH: number };
+
+/** The ordered section-root nodes of the page (top to bottom). Shared by the
+ *  validator (detectSections) and the generator's section splitter, so the gate's
+ *  section list and the emitted section components describe the same bands.
+ *  Falls back to `[ir.root]` when the page has no decomposable structure. */
+export function detectSectionNodes(ir: IR): IRNode[] {
+  const cw = ir.doc.canonicalViewport;
+  const ctx: Ctx = { cw, pageH: ir.doc.perViewport[cw]?.scrollHeight ?? 0 };
+  const bands = bandsOf(ir.root, 0, ctx);
+  // Stable sort by top edge; ties keep document order (a fixed nav stays before
+  // the hero it overlays).
+  bands.sort((a, b) => a.y - b.y);
+  // Nested wrappers can repeat the same box from disjoint subtrees — keep the first.
+  const final: Cand[] = [];
+  for (const c of bands) {
+    if (!final.some((f) => Math.abs(f.y - c.y) < 4 && Math.abs(f.height - c.height) < 4)) final.push(c);
+  }
+  if (final.length === 0) return [ir.root];
+  return final.map((c) => c.node);
+}
 
 export function detectSections(ir: IR): Section[] {
   const cw = ir.doc.canonicalViewport;
-  const vpWidth = cw;
-
-  const candidates: Cand[] = [];
-  const walk = (node: IRNode, path: string): void => {
-    const bbox = node.bboxByVp[cw];
-    const visible = node.visibleByVp[cw];
-    if (bbox && visible) {
-      const isSemantic = SEMANTIC.has(node.tag);
-      const isBigBlock = bbox.width >= vpWidth * 0.55 && bbox.height >= 64;
-      const display = node.computedByVp[cw]?.display ?? "";
-      const blockish = !/^(inline|inline-block|none)$/.test(display);
-      if ((isSemantic || isBigBlock) && blockish) {
-        candidates.push({ node, path, y: bbox.y, width: bbox.width, height: bbox.height });
-      }
-    }
-    for (const c of node.children) {
-      if (isTextChild(c)) continue;
-      walk(c, `${path}/${c.id}`);
-    }
-  };
-  walk(ir.root, ir.root.id);
-
-  // Outermost wins: drop candidates nested inside another candidate.
-  const byShallow = candidates.slice().sort((a, b) => a.path.split("/").length - b.path.split("/").length);
-  let kept: Cand[] = [];
-  for (const c of byShallow) {
-    if (kept.some((k) => c.path.startsWith(k.path + "/"))) continue;
-    kept.push(c);
-  }
-
-  // If the only survivor is a giant wrapper, expand into its section-like children.
-  const pageHeight = ir.doc.perViewport[cw]?.scrollHeight ?? 0;
-  kept = expandOversized(kept, vpWidth, pageHeight, cw);
-
-  // Sort by Y, then assign ids/roles.
-  kept.sort((a, b) => a.y - b.y || b.height - a.height);
-  // Deduplicate near-identical y/height wrappers (keep the first/shallowest).
-  const final: Cand[] = [];
-  for (const c of kept) {
-    const dup = final.find((f) => Math.abs(f.y - c.y) < 4 && Math.abs(f.height - c.height) < 4);
-    if (!dup) final.push(c);
-  }
-
-  return final.map((c, i) => ({
+  const pageH = ir.doc.perViewport[cw]?.scrollHeight ?? 0;
+  const nodes = detectSectionNodes(ir);
+  const roles = guessRoles(nodes, cw, pageH);
+  return nodes.map((node, i) => ({
     id: `section-${String(i + 1).padStart(3, "0")}`,
-    nodeId: c.node.id,
-    role: guessRole(c.node, i, final.length),
+    nodeId: node.id,
+    role: roles[i]!,
     order: i,
-    bboxByVp: bboxesFor(c.node),
+    bboxByVp: bboxesFor(node),
   }));
 }
 
-function expandOversized(cands: Cand[], vpWidth: number, pageHeight: number, cw: number): Cand[] {
-  if (cands.length > 2) return cands;
-  const threshold = Math.max(pageHeight * 0.55, 1200);
+/** Landmark evidence that a bar is site chrome: an ARIA landmark role on the node
+ *  itself, or a <nav> within a shallow wrapper chain. Lets a thin fixed bar (often a
+ *  62px styled <div> around the real <nav>) clear the semantic height bar. */
+export function navEvidence(node: IRNode): boolean {
+  const role = node.attrs.role ?? "";
+  if (role === "banner" || role === "navigation") return true;
+  return subtreeHas(node, (n) => n.tag === "nav" || n.attrs.role === "navigation", 3);
+}
+
+function candOf(node: IRNode, ctx: Ctx): Cand | null {
+  const bbox = node.bboxByVp[ctx.cw];
+  if (!bbox || !node.visibleByVp[ctx.cw]) return null;
+  const display = node.computedByVp[ctx.cw]?.display ?? "";
+  if (/^(inline|inline-block|none)$/.test(display)) return null;
+  if (bbox.width < ctx.cw * MIN_BAND_W_FRAC) return null;
+  const minH = SEMANTIC.has(node.tag) || navEvidence(node) ? MIN_SEMANTIC_H : MIN_BAND_H;
+  if (bbox.height < minH) return null;
+  return { node, y: bbox.y, width: bbox.width, height: bbox.height };
+}
+
+/** Collect the band candidates among `container`'s children. A band-sized child is
+ *  kept; a page-covering child is descended into (its children replace it only when
+ *  they tile it — see acceptSplit); anything else is a transparent wrapper we look
+ *  through. Output is in document order. */
+function bandsOf(container: IRNode, depth: number, ctx: Ctx): Cand[] {
+  if (depth > MAX_DEPTH) return [];
   const out: Cand[] = [];
-  for (const c of cands) {
-    if (c.height < threshold) { out.push(c); continue; }
-    const inner: Cand[] = [];
-    const collect = (node: IRNode, path: string, depth: number): void => {
-      if (depth > 6) return;
-      for (const ch of node.children) {
-        if (isTextChild(ch)) continue;
-        const bbox = ch.bboxByVp[cw];
-        if (bbox && ch.visibleByVp[cw] && bbox.width >= vpWidth * 0.5 && bbox.height >= 64) {
-          inner.push({ node: ch, path: `${path}/${ch.id}`, y: bbox.y, width: bbox.width, height: bbox.height });
-        } else {
-          collect(ch, `${path}/${ch.id}`, depth + 1);
-        }
-      }
-    };
-    collect(c.node, c.path, 0);
-    // outermost wins within inner
-    const byShallow = inner.slice().sort((a, b) => a.path.split("/").length - b.path.split("/").length);
-    const keptInner: Cand[] = [];
-    for (const ic of byShallow) {
-      if (keptInner.some((k) => ic.path.startsWith(k.path + "/"))) continue;
-      keptInner.push(ic);
+  for (const child of container.children) {
+    if (isTextChild(child)) continue;
+    const cand = candOf(child, ctx);
+    if (!cand) {
+      out.push(...bandsOf(child, depth + 1, ctx));
+      continue;
     }
-    if (keptInner.length >= 3) out.push(...keptInner);
-    else out.push(c);
+    if (ctx.pageH > 0 && cand.height > ctx.pageH * WRAPPER_FRAC) {
+      const inner = bandsOf(child, depth + 1, ctx);
+      if (acceptSplit(inner, cand)) {
+        out.push(...inner);
+        continue;
+      }
+    }
+    out.push(cand);
   }
   return out;
 }
 
-function guessRole(node: IRNode, index: number, total: number): string {
-  if (node.tag === "header") return "header";
-  if (node.tag === "nav") return "nav";
-  if (node.tag === "footer") return "footer";
-  if (node.tag === "main") return "main";
-  if (index === 0) return "hero";
-  if (index === total - 1) return "footer";
-  return "section";
+/** May `inner` replace its containing candidate? Only when it reads as a stack of
+ *  bands: at least two, not a fragmentation explosion, vertically stacked (side-by-side
+ *  columns or overlaid layers must not be split), and tiling the container with
+ *  near-complete coverage so no substantial content is silently dropped. */
+function acceptSplit(inner: Cand[], parent: Cand): boolean {
+  if (inner.length < 2 || inner.length > MAX_BANDS_PER_SPLIT) return false;
+  const sorted = inner.slice().sort((a, b) => a.y - b.y);
+  for (let i = 1; i < sorted.length; i++) {
+    const prev = sorted[i - 1]!, cur = sorted[i]!;
+    const overlap = prev.y + prev.height - cur.y;
+    if (overlap > Math.min(prev.height, cur.height) * MAX_STACK_OVERLAP) return false;
+  }
+  let covered = 0, cursor = -Infinity;
+  for (const c of sorted) {
+    const top = Math.max(c.y, cursor), bot = c.y + c.height;
+    if (bot > top) covered += bot - top;
+    cursor = Math.max(cursor, bot);
+  }
+  return covered >= parent.height * MIN_CHILD_COVERAGE;
+}
+
+function subtreeHas(node: IRNode, pred: (n: IRNode) => boolean, depth = 6): boolean {
+  if (depth < 0) return false;
+  for (const c of node.children) {
+    if (isTextChild(c)) continue;
+    if (pred(c) || subtreeHas(c, pred, depth - 1)) return true;
+  }
+  return false;
+}
+
+/** A <header> that carries the page's h1 and real height is the hero band, not
+ *  site chrome — "header → chrome" only holds for the thin bar variant. */
+export function heroLikeHeader(node: IRNode, cw: number): boolean {
+  const h = node.bboxByVp[cw]?.height ?? 0;
+  return h >= 200 && subtreeHas(node, (n) => n.tag === "h1");
+}
+
+/** Advisory roles, one pass top-to-bottom: tag evidence first, then the first
+ *  near-top content band claims "hero" (once), then content evidence. */
+function guessRoles(nodes: IRNode[], cw: number, pageH: number): string[] {
+  let heroClaimed = false;
+  return nodes.map((node, index) => {
+    if (node.tag === "nav") return "navbar";
+    if (node.tag === "header") {
+      if (!heroLikeHeader(node, cw)) return "header";
+      heroClaimed = true;
+      return "hero";
+    }
+    if (node.tag === "footer") return "footer";
+    if (node.tag === "aside") return "aside";
+    if (node.tag === "main") return "main";
+    const bbox = node.bboxByVp[cw];
+    const h = bbox?.height ?? 0, y = bbox?.y ?? 0;
+    // thin top bar without the <nav> tag (first band, or a fixed bar with landmark evidence)
+    if (h <= 140 && y <= 160 && (index === 0 || navEvidence(node))) return "navbar";
+    if (!heroClaimed && (bbox?.y ?? 0) <= Math.max(900, pageH * 0.25)) {
+      heroClaimed = true;
+      return "hero";
+    }
+    if (index === nodes.length - 1) return "footer";
+    if (subtreeHas(node, (n) => n.tag === "form")) return "contact";
+    if (subtreeHas(node, (n) => n.tag === "video" || n.tag === "iframe")) return "media";
+    return "section";
+  });
 }
 
 function bboxesFor(node: IRNode): Section["bboxByVp"] {
diff --git a/compiler/src/infer/semanticTokens.ts b/compiler/src/infer/semanticTokens.ts
index 10bc0bb..a68eaa0 100644
--- a/compiler/src/infer/semanticTokens.ts
+++ b/compiler/src/infer/semanticTokens.ts
@@ -27,12 +27,117 @@ export type ColorPalette = {
 const TRANSPARENT = new Set(["rgba(0, 0, 0, 0)", "transparent", "rgba(0,0,0,0)", ""]);
 
 type RGBA = [number, number, number, number];
+
+/** Parse the numeric args of a `fn(a b c / d)` / `fn(a,b,c,d)` color into [a,b,c,alpha].
+ *  Percentages resolve against `pctBase` (255 for rgb channels, 1 for lab/lch/oklab/oklch
+ *  L and the c/ab axes where the caller passes their own scale). `none` → 0. */
+function parseColorArgs(inner: string): { nums: number[]; alpha: number } | null {
+  const parts = inner.split("/");
+  const main = parts[0]!.trim().split(/[\s,]+/).filter(Boolean);
+  const nums = main.map((s) => (s === "none" ? 0 : parseFloat(s)));
+  if (nums.length < 3 || nums.slice(0, 3).some(Number.isNaN)) return null;
+  let alpha = 1;
+  const alphaTok = parts.length > 1 ? parts[1]!.trim() : main[3];
+  if (alphaTok !== undefined && alphaTok !== "none") {
+    const a = alphaTok.endsWith("%") ? parseFloat(alphaTok) / 100 : parseFloat(alphaTok);
+    if (!Number.isNaN(a)) alpha = a;
+  }
+  return { nums, alpha };
+}
+
+function pctOr(tok: string, base: number): number {
+  return tok.endsWith("%") ? (parseFloat(tok) / 100) * base : parseFloat(tok);
+}
+
+/** Linear-light sRGB channel → gamma-encoded 0–255. */
+function lin2srgb(c: number): number {
+  const v = c <= 0.0031308 ? 12.92 * c : 1.055 * Math.pow(c, 1 / 2.4) - 0.055;
+  return Math.round(Math.min(1, Math.max(0, v)) * 255);
+}
+
+/** OKLab → sRGB (CSS Color 4 reference matrices). Returns gamma-encoded 0–255. */
+function oklabToRgb(L: number, a: number, b: number): [number, number, number] {
+  const l_ = L + 0.3963377774 * a + 0.2158037573 * b;
+  const m_ = L - 0.1055613458 * a - 0.0638541728 * b;
+  const s_ = L - 0.0894841775 * a - 1.2914855480 * b;
+  const l = l_ ** 3, m = m_ ** 3, s = s_ ** 3;
+  const r = +4.0767416621 * l - 3.3077115913 * m + 0.2309699292 * s;
+  const g = -1.2684380046 * l + 2.6097574011 * m - 0.3413193965 * s;
+  const bl = -0.0041960863 * l - 0.7034186147 * m + 1.7076147010 * s;
+  return [lin2srgb(r), lin2srgb(g), lin2srgb(bl)];
+}
+
+/** CIE Lab (D50) → sRGB, gamma-encoded 0–255. */
+function labToRgb(L: number, a: number, b: number): [number, number, number] {
+  const fy = (L + 16) / 116, fx = fy + a / 500, fz = fy - b / 200;
+  const d = 6 / 29;
+  const inv = (t: number): number => (t > d ? t ** 3 : 3 * d * d * (t - 4 / 29));
+  // D50 white point.
+  const X = 0.9642956 * inv(fx), Y = 1.0 * inv(fy), Z = 0.8251046 * inv(fz);
+  // XYZ(D50) → linear sRGB (Bradford-adapted D50→D65 folded in).
+  const r = +3.1341359 * X - 1.6172206 * Y - 0.4906860 * Z;
+  const g = -0.9787684 * X + 1.9161415 * Y + 0.0334540 * Z;
+  const bl = +0.0719453 * X - 0.2289914 * Y + 1.4052427 * Z;
+  return [lin2srgb(r), lin2srgb(g), lin2srgb(bl)];
+}
+
+/** Parse any CSS color value (`rgb`/`rgba`/`hsl`/`hsla`/`oklab`/`oklch`/`lab`/`lch`/hex/
+ *  named-ish) into rounded sRGB `[r,g,b,alpha]`, else null. The literal value is kept
+ *  verbatim in emitted CSS; this RGB is used ONLY for clustering (grader works in sRGB
+ *  ±2), so oklab/lch colours cluster + earn semantic roles instead of falling to --clr-N. */
+function parseColor(v: string): RGBA | null {
+  const s = v.trim().toLowerCase();
+  if (s === "white") return [255, 255, 255, 1];
+  if (s === "black") return [0, 0, 0, 1];
+  const hex = /^#([0-9a-f]{3,8})$/i.exec(s);
+  if (hex) {
+    let h = hex[1]!;
+    if (h.length === 3 || h.length === 4) h = h.split("").map((c) => c + c).join("");
+    const r = parseInt(h.slice(0, 2), 16), g = parseInt(h.slice(2, 4), 16), b = parseInt(h.slice(4, 6), 16);
+    const a = h.length >= 8 ? parseInt(h.slice(6, 8), 16) / 255 : 1;
+    return [r, g, b, a];
+  }
+  const fn = /^(rgba?|hsla?|oklab|oklch|lab|lch)\(([^)]*)\)$/i.exec(s);
+  if (!fn) return null;
+  const kind = fn[1]!, parsed = parseColorArgs(fn[2]!);
+  if (!parsed) return null;
+  const { nums, alpha } = parsed;
+  const raw = fn[2]!.split("/")[0]!.trim().split(/[\s,]+/).filter(Boolean);
+  if (kind.startsWith("rgb")) {
+    return [Math.round(pctOr(raw[0]!, 255)), Math.round(pctOr(raw[1]!, 255)), Math.round(pctOr(raw[2]!, 255)), alpha];
+  }
+  if (kind.startsWith("hsl")) {
+    const H = ((nums[0]! % 360) + 360) % 360, S = pctOr(raw[1]!, 1), Lh = pctOr(raw[2]!, 1);
+    const c = (1 - Math.abs(2 * Lh - 1)) * S, x = c * (1 - Math.abs(((H / 60) % 2) - 1)), m = Lh - c / 2;
+    const [r1, g1, b1] = H < 60 ? [c, x, 0] : H < 120 ? [x, c, 0] : H < 180 ? [0, c, x] : H < 240 ? [0, x, c] : H < 300 ? [x, 0, c] : [c, 0, x];
+    return [Math.round((r1 + m) * 255), Math.round((g1 + m) * 255), Math.round((b1 + m) * 255), alpha];
+  }
+  if (kind === "oklab") { const [r, g, b] = oklabToRgb(pctOr(raw[0]!, 1), nums[1]!, nums[2]!); return [r, g, b, alpha]; }
+  if (kind === "oklch") {
+    const L = pctOr(raw[0]!, 1), C = nums[1]!, h = (nums[2]! * Math.PI) / 180;
+    const [r, g, b] = oklabToRgb(L, C * Math.cos(h), C * Math.sin(h)); return [r, g, b, alpha];
+  }
+  if (kind === "lab") { const [r, g, b] = labToRgb(pctOr(raw[0]!, 100), nums[1]!, nums[2]!); return [r, g, b, alpha]; }
+  if (kind === "lch") {
+    const L = pctOr(raw[0]!, 100), C = nums[1]!, h = (nums[2]! * Math.PI) / 180;
+    const [r, g, b] = labToRgb(L, C * Math.cos(h), C * Math.sin(h)); return [r, g, b, alpha];
+  }
+  return null;
+}
+
+/** Back-compat alias: the palette parses every colour space now, not just rgb(). */
 function parseRgb(v: string): RGBA | null {
-  const m = v.match(/rgba?\(([^)]+)\)/i);
-  if (!m) return null;
-  const p = m[1]!.split(/[,\/]/).map((s) => parseFloat(s.trim()));
-  if (p.length < 3 || p.slice(0, 3).some(Number.isNaN)) return null;
-  return [Math.round(p[0]!), Math.round(p[1]!), Math.round(p[2]!), p.length >= 4 && !Number.isNaN(p[3]!) ? p[3]! : 1];
+  return parseColor(v);
+}
+
+/** A stable clustering key for a color literal: its rounded sRGB (+ alpha), so two literals
+ *  that render the same colour (`oklab(0.988242 …)` and `oklab(0.988371 …)` → rgb(251,251,251))
+ *  collapse to ONE minted token instead of a wall of near-identical --clr-N. Null when the
+ *  value can't be parsed (keeps the raw literal as its own key). Alpha bucketed to ±0.02. */
+export function colorClusterKey(v: string): string | null {
+  const c = parseColor(v);
+  if (!c) return null;
+  return `${c[0]},${c[1]},${c[2]},${Math.round(c[3] * 50)}`;
 }
 function within2(a: RGBA, b: RGBA): boolean {
   return Math.abs(a[0] - b[0]) <= 2 && Math.abs(a[1] - b[1]) <= 2 && Math.abs(a[2] - b[2]) <= 2 && Math.abs(a[3] - b[3]) <= 0.04;
@@ -140,33 +245,57 @@ function paletteFrom(usage: Map<string, Usage>, roleIr: IR, minCount: number): C
   const fgCluster = findCluster(pv?.bodyColor);
   if (fgCluster) assign("--foreground", fgCluster);
 
-  // 2) Primary/accent: most-used chromatic color, weighted toward interactive usage.
-  const remaining = clusters.filter((c) => !c.members.some((m) => valueToName.has(m)));
+  // Luminance (0–1) for deterministic tiebreaks (Rec.709). Ties in every ranking below
+  // break by count, then luminance (dark→light), then the literal value — so the palette
+  // is byte-stable for a given capture (determinism gate 6).
+  const lum = (c: Usage): number => (0.2126 * c.rgba[0] + 0.7152 * c.rgba[1] + 0.0722 * c.rgba[2]) / 255;
+  const unnamed = (c: { canon: Usage; members: string[] }): boolean => !c.members.some((m) => valueToName.has(m));
+  const byCount = (score: (c: Usage) => number) => (a: { canon: Usage }, b: { canon: Usage }): number =>
+    score(b.canon) - score(a.canon) || b.canon.count - a.canon.count || lum(a.canon) - lum(b.canon) || a.canon.value.localeCompare(b.canon.value);
+
+  // 2) Brand + accent: the most-used chromatic colours, weighted toward interactive usage
+  //    (buttons/links). `--primary` (a.k.a. brand) is the strongest; `--accent` the next.
+  //    A colour is "chromatic" only with real hue: HSL saturation ≥ 0.25 AND an absolute
+  //    channel spread ≥ 24, so near-neutral off-whites/creams (max−min ≈ 10) that merely
+  //    tip over the ratio threshold stay neutrals → --surface, not a fake --accent.
+  const chroma = (c: RGBA): number => Math.max(c[0], c[1], c[2]) - Math.min(c[0], c[1], c[2]);
+  const remaining = clusters.filter(unnamed);
   const chromatic = remaining
-    .filter((c) => { const { s } = satLight(c.canon.rgba); return s >= 0.25; })
-    .sort((a, b) => (b.canon.interactive * 3 + b.canon.count) - (a.canon.interactive * 3 + a.canon.count));
+    .filter((c) => satLight(c.canon.rgba).s >= 0.25 && chroma(c.canon.rgba) >= 24)
+    .sort(byCount((c) => c.interactive * 3 + c.count));
   if (chromatic[0]) assign("--primary", chromatic[0]);
   if (chromatic[1]) assign("--accent", chromatic[1]);
 
-  // 3) Border: most-used color that appears predominantly as a border.
+  // 3) Border: most-used colour that appears predominantly as a border.
   const borderC = remaining
-    .filter((c) => !c.members.some((m) => valueToName.has(m)) && c.canon.border > 0)
-    .sort((a, b) => b.canon.border - a.canon.border)[0];
+    .filter((c) => unnamed(c) && c.canon.border > 0)
+    .sort(byCount((c) => c.border))[0];
   if (borderC && borderC.canon.border >= Math.max(2, minCount - 1)) assign("--border", borderC);
 
-  // 4) Neutrals: a light neutral used as a background → surface; a mid neutral text → muted.
-  for (const c of remaining) {
-    if (c.members.some((m) => valueToName.has(m))) continue;
-    if (c.canon.count < minCount) continue;
-    const { s, l } = satLight(c.canon.rgba);
-    if (s < 0.15 && c.canon.bg >= c.canon.text && l > 0.85 && !taken.has("--surface")) assign("--surface", c);
-    else if (s < 0.2 && c.canon.text >= c.canon.bg && l > 0.35 && l < 0.7 && !taken.has("--muted-foreground")) assign("--muted-foreground", c);
+  // 4) Neutrals, ranked so the most-used earns the cleanest name. Light neutrals used as
+  //    backgrounds → --surface, --surface-2, … (section/card/footer alt backgrounds);
+  //    mid/dark neutrals used as text → --muted-foreground then --muted. "Neutral" is the
+  //    complement of "chromatic" above (no strong hue: low saturation OR tiny channel spread),
+  //    so no colour falls through the gap between the two thresholds.
+  const neutrals = remaining
+    .filter((c) => unnamed(c) && c.canon.count >= minCount && (satLight(c.canon.rgba).s < 0.25 || chroma(c.canon.rgba) < 24))
+    .sort(byCount((c) => c.count));
+  let surfaceN = 0;
+  for (const c of neutrals) {
+    if (!unnamed(c)) continue;
+    const { l } = satLight(c.canon.rgba);
+    if (c.canon.bg >= c.canon.text && l > 0.85) {
+      assign(surfaceN === 0 ? "--surface" : `--surface-${surfaceN + 1}`, c);
+      surfaceN++;
+    } else if (c.canon.text >= c.canon.bg && l > 0.2 && l < 0.7) {
+      assign(!taken.has("--muted-foreground") ? "--muted-foreground" : "--muted", c);
+    }
   }
 
-  // 5) Everything else used >= minCount → numbered.
+  // 5) Everything else used >= minCount → numbered, in a deterministic order.
   let ci = 1;
-  for (const c of remaining) {
-    if (c.members.some((m) => valueToName.has(m))) continue;
+  for (const c of [...remaining].sort(byCount(() => 0))) {
+    if (!unnamed(c)) continue;
     if (c.canon.count < minCount) continue;
     assign(`--color-${String(ci++).padStart(3, "0")}`, c);
   }
diff --git a/compiler/src/normalize/ir.ts b/compiler/src/normalize/ir.ts
index 0fba954..8c72bcb 100644
--- a/compiler/src/normalize/ir.ts
+++ b/compiler/src/normalize/ir.ts
@@ -6,7 +6,10 @@ import type { InteractionCapture } from "../capture/interactions.js";
 /**
  * Normalized Render IR. Merges the per-viewport capture snapshots into a single
  * tree whose structure comes from the canonical (1280) capture; each node carries
- * per-viewport computed styles, bounding boxes, and visibility. This is the single
+ * per-viewport computed styles, bounding boxes, and visibility. Children that exist
+ * ONLY at non-canonical viewports are grafted in as siblings (visible only in their
+ * source bands); a container whose children are a wholly different set at some width
+ * is recorded as content drift instead (see childDriftVps). This is the single
  * source of truth for section/token inference, generation, and validation.
  */
 
@@ -25,6 +28,9 @@ export type IRNode = {
   // element had no class.
   srcClass?: string;
   rawHTML?: string; // inline svg
+  // Computed paint of an inline <svg> root (fill/stroke/color), carried from capture. Lets codegen
+  // recover a paint that a raw `fill="none"` attribute hides but site CSS actually supplied.
+  svgPaint?: { fill: string; stroke: string; color: string };
   visibleByVp: Record<number, boolean>;
   bboxByVp: Record<number, BBox>;
   computedByVp: Record<number, StyleMap>;
@@ -37,6 +43,14 @@ export type IRNode = {
   // ::placeholder computed style (input/textarea with placeholder text) — emitted as a
   // `::placeholder` rule so form controls keep their authored placeholder color.
   placeholderByVp?: Record<number, StyleMap>;
+  // Band viewports where this container's element children were a DIFFERENT SET than the
+  // canonical capture's (mutual whole-set mismatch — the source deterministically served
+  // different content at that width, e.g. a rotator picking other items per breakpoint).
+  // Policy: FAITHFUL-AT-CANONICAL — emission shows the canonical children there (it skips
+  // the display:none band it would otherwise emit for a child with no counterpart) instead
+  // of rendering an empty shell; the other set is NOT grafted (no duplication). Surfaced in
+  // the manifest via doc.contentDrift.
+  childDriftVps?: number[];
   children: IRChild[];
 };
 
@@ -72,6 +86,11 @@ export type IRDoc = {
   // re-emit the keyframes that the per-node `animation-name` declarations reference —
   // without these the animation properties are inert (the half-plumbed pre-Stage-5 gap).
   keyframes: string[];
+  // Containers whose children diverged as a WHOLE SET at some band viewport(s) (see
+  // IRNode.childDriftVps). Recorded post-renumber so ids are final; carried into the
+  // generated manifest as a fidelity note ("the source served different content there").
+  // Omitted when no drift was detected.
+  contentDrift?: Array<{ id: string; tag: string; viewports: number[] }>;
 };
 
 export type IR = {
@@ -83,6 +102,33 @@ export function isTextChild(c: IRChild): c is IRTextNode {
   return (c as IRTextNode).text !== undefined;
 }
 
+/**
+ * In-flow content extent at a viewport: the largest border-box bottom (`bbox.y + bbox.height`)
+ * over every VISIBLE, IN-FLOW descendant. This is the true height the real page laid out to,
+ * independent of a scroll-lock that clips the root to one viewport (a popup vendor that sets
+ * `body{overflow:hidden;height:100vh}` collapses `document.scrollHeight` to the viewport, but
+ * the in-flow sections still carry their real coordinates). Out-of-flow (absolute/fixed) and
+ * floated boxes are excluded — a fixed overlay/footer badge or a floated aside is not part of
+ * the document flow that determines page height. Pure + deterministic (reads only the IR).
+ */
+export function irContentExtent(root: IRNode, vp: number): number {
+  let maxBottom = 0;
+  const visit = (n: IRNode): void => {
+    for (const c of n.children) {
+      if (isTextChild(c)) continue;
+      const cs = c.computedByVp[vp];
+      const bb = c.bboxByVp[vp];
+      if (!cs || !bb || !c.visibleByVp[vp]) { visit(c); continue; }
+      const pos = cs.position || "static";
+      const inFlow = pos !== "absolute" && pos !== "fixed" && (cs.float || "none") === "none";
+      if (inFlow) maxBottom = Math.max(maxBottom, bb.y + bb.height);
+      visit(c);
+    }
+  };
+  visit(root);
+  return maxBottom;
+}
+
 /**
  * Recover lazy-loaded CSS backgrounds dropped by uneven per-viewport capture.
  * If an element has exactly one URL background at some sampled widths and
@@ -175,9 +221,24 @@ const NOISE_TAGS = new Set(["next-route-announcer"]);
 // width where capture happened to read it open → an empty 400×700 white rectangle at 2xl). Drop
 // the whole subtree so it never reaches generation.
 const THIRD_PARTY_OVERLAY = /(?:^|[\s_-])(?:intercom|drift-|hubspot-messages|zendesk|zd-|onetrust|ot-sdk-|usercentrics|grecaptcha|crisp-client|tawk-|livechat|helpscout|beacon-container|cookiebot|cky-)/;
+
+/**
+ * Email-capture / promo POPUP overlay containers (Attentive, Wunderkind/Bounce Exchange,
+ * Justuno, Privy, Omnisend, Sailthru, Wisepops, etc.). These vendors inject a full-viewport
+ * fixed overlay + backdrop that scroll-locks the page — third-party chrome, not site content.
+ *
+ * CAUTION: these vendors ALSO ship inline, embedded signup forms that ARE real page content
+ * and are deliberately grafted (see iframeGraft tests). So this matches ONLY the OVERLAY
+ * CONTAINER markers each vendor uses for its popup (`attentive_overlay`, `bx-wrapper` /
+ * `wk-`, `justuno`-`container`, `privy-`popup, …) — never a bare vendor name that an inline
+ * form embed would also carry. Overlay-container tokens only.
+ */
+export const POPUP_OVERLAY_CONTAINER =
+  /(?:^|[\s_-])(?:attentive_overlay|attentive_creative|attn-|bx-wrapper|bx-window|bounce-?exchange|wknd-|wunderkind|justuno_container|jw-overlay|privy-popup|privy-container|klaviyo-form-.*overlay|sailthru-overlay|wisepops-root|recart-popup|recart-modal)/;
 function isThirdPartyOverlay(raw: RawNode): boolean {
   const idClass = `${raw.attrs?.id ?? ""} ${raw.attrs?.class ?? ""}`.toLowerCase();
   if (THIRD_PARTY_OVERLAY.test(idClass)) return true;
+  if (POPUP_OVERLAY_CONTAINER.test(idClass)) return true;
   // INT_MAX band: overlay libraries stack above everything. Real content should not reach here,
   // so this cannot swallow site chrome under normal captures.
   const zi = parseInt(raw.computed?.zIndex ?? "", 10);
@@ -188,6 +249,121 @@ function elementChildren(n: RawNode): RawNode[] {
   return n.children.filter((c) => (c as { text?: string }).text === undefined) as RawNode[];
 }
 
+/** True for a transform value that is visually the identity (no offset/rotation/scale):
+ *  the `none` keyword or an identity matrix/matrix3d the browser reports as noise. */
+export function isIdentityTransform(value: string | undefined): boolean {
+  if (!value || value === "none") return true;
+  const m = /^matrix\(([^)]*)\)$/.exec(value.trim());
+  if (m) {
+    const n = m[1]!.split(",").map((s) => parseFloat(s.trim()));
+    return n.length === 6 && n[0] === 1 && n[1] === 0 && n[2] === 0 && n[3] === 1 && n[4] === 0 && n[5] === 0;
+  }
+  const m3 = /^matrix3d\(([^)]*)\)$/.exec(value.trim());
+  if (m3) {
+    const n = m3[1]!.split(",").map((s) => parseFloat(s.trim()));
+    const id = [1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1];
+    return n.length === 16 && n.every((v, i) => v === id[i]);
+  }
+  return false;
+}
+
+/** Parse a CSS length to px (number), 0 for `auto`/empty/non-px. */
+function pfLen(v: string | undefined): number {
+  if (!v) return 0;
+  const n = parseFloat(v);
+  return Number.isFinite(n) ? n : 0;
+}
+
+/** The horizontal translate (matrix `e`) of a computed transform, or null if the transform is not a
+ *  pure-2D matrix/matrix3d with a definite tx (rotation/scale/skew or 3D perspective → null: we only
+ *  re-anchor plain horizontal track offsets). `matrix(a,b,c,d,e,f)` → e; `matrix3d(...)` → m41. */
+function translateXOf(value: string | undefined): number | null {
+  if (!value || value === "none") return null;
+  const m = /^matrix\(([^)]*)\)$/.exec(value.trim());
+  if (m) {
+    const n = m[1]!.split(",").map((s) => parseFloat(s.trim()));
+    if (n.length !== 6 || n.some((x) => !Number.isFinite(x))) return null;
+    if (n[1] !== 0 || n[2] !== 0) return null;               // has rotation/skew → not a plain slide
+    return n[4]!;
+  }
+  const m3 = /^matrix3d\(([^)]*)\)$/.exec(value.trim());
+  if (m3) {
+    const n = m3[1]!.split(",").map((s) => parseFloat(s.trim()));
+    if (n.length !== 16 || n.some((x) => !Number.isFinite(x))) return null;
+    // Require an otherwise-identity 3D matrix apart from the translate column (indices 12/13/14).
+    const idExceptTranslate = [1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, /*12*/ 0, /*13*/ 0, /*14*/ 0, 1];
+    for (let i = 0; i < 16; i++) { if (i === 12 || i === 13 || i === 14) continue; if (n[i] !== idExceptTranslate[i]) return null; }
+    return n[12]!;
+  }
+  return null;
+}
+
+/** Return `value` with its horizontal translate replaced by `tx` (keeps the rest of the matrix). */
+function setTranslateX(value: string, tx: number): string {
+  const m = /^matrix\(([^)]*)\)$/.exec(value.trim());
+  if (m) {
+    const n = m[1]!.split(",").map((s) => s.trim());
+    n[4] = String(tx);
+    return `matrix(${n.join(", ")})`;
+  }
+  const m3 = /^matrix3d\(([^)]*)\)$/.exec(value.trim());
+  if (m3) {
+    const n = m3[1]!.split(",").map((s) => s.trim());
+    n[12] = String(tx);
+    return `matrix3d(${n.join(", ")})`;
+  }
+  return value;
+}
+
+/**
+ * Normalize per-viewport transform values so identity is represented uniformly as the literal
+ * `none`. Two problems this closes, both in the per-viewport delta emission downstream:
+ *   1. The browser reports "no transform" inconsistently — `none` at some widths, an identity
+ *      `matrix(1,0,0,1,0,0)` at others (composited-layer noise). The generator's default-skip
+ *      only recognizes `none`, so an identity matrix at the base viewport is emitted as a real
+ *      transform and then cascades across bands.
+ *   2. When ANY viewport carries a genuine (non-identity) transform, the identity value at the
+ *      other viewports must stay observable — canonicalizing it to `none` (not dropping it) lets
+ *      the generator emit the explicit reset so the non-identity transform can't leak into a band
+ *      where the source had none.
+ * Deterministic, in place; only touches the `transform` slot.
+ */
+export function canonicalizeTransforms(computedByVp: Record<number, StyleMap>): void {
+  for (const k of Object.keys(computedByVp)) {
+    const cs = computedByVp[Number(k)];
+    if (cs && isIdentityTransform(cs.transform)) cs.transform = "none";
+  }
+}
+
+/** True when an INFINITE CSS animation is active at this viewport. Such an animation perpetually
+ *  drives its animated properties (opacity/transform), so the captured value is a frozen phase of
+ *  the loop, not authored design. */
+function hasInfiniteAnimation(cs: StyleMap | undefined): boolean {
+  if (!cs || (cs.animationName || "none") === "none") return false;
+  return /infinite/.test(cs.animationIterationCount || "1");
+}
+
+/**
+ * Neutralize the transform of a node that carries an INFINITE animation at ANY captured viewport.
+ * The capture shutter froze the marquee/spinner mid-loop, and — critically — a CSS animation gated
+ * to a breakpoint (Webflow's `max-lg` logo/big-text tracks) reads `animation:none` at the widths
+ * where it does NOT run, yet the browser still reports the last frozen `translateX` there. Banding
+ * those frozen values bakes a mid-scroll offset that shifts content offscreen-left AT REST (rows
+ * starting mid-glyph). The runtime `@keyframes` owns the transform and starts at translateX(0), so
+ * the faithful at-rest value is `none` at every width; generation's `animOwnedProps` then keeps the
+ * base holding while the animation drives it live. Only fires when a genuine infinite animation is
+ * present at some viewport — a statically-offset design element (no animation) is untouched.
+ * Deterministic, in place; only touches the `transform` slot.
+ */
+export function neutralizeAnimatedTransforms(computedByVp: Record<number, StyleMap>): void {
+  const vps = Object.keys(computedByVp).map(Number);
+  if (!vps.some((vp) => hasInfiniteAnimation(computedByVp[vp]))) return;
+  for (const vp of vps) {
+    const cs = computedByVp[vp];
+    if (cs && cs.transform && cs.transform !== "none") cs.transform = "none";
+  }
+}
+
 /** Full identity signature (tag + id + class). */
 function sigFull(n: RawNode): string {
   return `${n.tag}#${n.attrs?.id ?? ""}.${(n.attrs?.class ?? "").trim()}`;
@@ -259,6 +435,39 @@ function alignChildren(canon: RawNode[], other: RawNode[]): (RawNode | undefined
   return out;
 }
 
+/** True when this raw node or any element descendant painted at its capture viewport. */
+function rawSubtreeVisible(n: RawNode): boolean {
+  if (n.visible) return true;
+  for (const c of elementChildren(n)) if (rawSubtreeVisible(c)) return true;
+  return false;
+}
+
+/** Most frequent tag in a sibling group (ties broken alphabetically — deterministic). */
+function dominantTag(nodes: RawNode[]): string {
+  const counts = new Map<string, number>();
+  for (const n of nodes) counts.set(n.tag, (counts.get(n.tag) ?? 0) + 1);
+  let best = "", bestC = -1;
+  for (const [t, c] of [...counts.entries()].sort((a, b) => (a[0] < b[0] ? -1 : 1))) {
+    if (c > bestC) { best = t; bestC = c; }
+  }
+  return best;
+}
+
+// A sibling appearing ONLY at non-canonical viewport(s) is grafted into the IR (visible only in
+// its source band(s)). Cap per parent per viewport so a pathological capture (a virtualized list
+// re-keying hundreds of rows) can't balloon the tree; the whole-set drift path below covers the
+// legitimate large-mismatch case.
+const GRAFT_MAX_PER_VP = 24;
+// Whole-set content-identity drift: at least this many children UNMATCHED on BOTH sides before a
+// container is treated as "the source served different content at this width" (vs a couple of
+// responsive-only extras, which are grafted instead).
+const DRIFT_MIN_UNMATCHED = 3;
+
+/** A per-parent graft group: one non-canonical-only child, matched across the non-canonical
+ *  viewports it appears at. `rep` is the raw node from the LOWEST viewport (structural identity
+ *  for aligning later viewports into the group). */
+type GraftGroup = { rep: RawNode; rawByVp: Record<number, RawNode> };
+
 /** Capture-ids of recognized-pattern panels/regions to force-keep through pruning
  *  (they are display:none in the inactive/collapsed base state). Empty when no
  *  interactions were captured, so non-interactive runs prune exactly as before. */
@@ -289,6 +498,9 @@ export function buildIR(sourceDir: string, viewports: number[], opts?: { motion?
   }
   const canonical = viewports.includes(1280) ? 1280 : viewports[Math.floor(viewports.length / 2)]!;
   const canonSnap = snapshots[canonical]!;
+  // Deterministic iteration order for the cross-viewport graft grouping below.
+  const vpsAsc = [...viewports].sort((a, b) => a - b);
+  const bandVpSet = new Set(bandVps);
 
   // Stage 4: recognized interactive panels (tabs/accordion) are often display:none
   // at base (the inactive/collapsed state). Their subtrees must survive pruning so
@@ -304,6 +516,10 @@ export function buildIR(sourceDir: string, viewports: number[], opts?: { motion?
   const convert = (raw: RawNode, matched: Record<number, RawNode | undefined>): IRNode | null => {
     if (NOISE_TAGS.has(raw.tag)) return null;
     if (isThirdPartyOverlay(raw)) return null;
+    // Font-metric / measurement scratch nodes the source's own JS injects (tagged by the walker):
+    // absolutely positioned, parked far off-screen, non-painting. Never user-visible — drop so they
+    // don't ship as page markup (e.g. the `<div … -top-[6249rem] invisible>Mgy</div>` probe).
+    if (raw.probe) return null;
 
     const visibleByVp: Record<number, boolean> = {};
     const bboxByVp: Record<number, BBox> = {};
@@ -324,6 +540,14 @@ export function buildIR(sourceDir: string, viewports: number[], opts?: { motion?
       if (match.after) afterByVp[vw] = match.after;
       if (match.placeholder) placeholderByVp[vw] = match.placeholder;
     }
+    // Canonicalize identity transforms (none / identity matrix) to `none` at every viewport so
+    // the generator's per-band delta treats them uniformly and a scroll/composite-noise transform
+    // at one width can't leak across bands.
+    canonicalizeTransforms(computedByVp);
+    // Drop transforms frozen mid-loop by an infinite animation (marquees/spinners) at every viewport —
+    // including the breakpoints where the animation is gated off but the browser still reports the last
+    // frozen offset. Prevents a baked mid-scroll translateX from clipping content offscreen at rest.
+    neutralizeAnimatedTransforms(computedByVp);
 
     const node: IRNode = {
       id: nextId(),
@@ -335,6 +559,7 @@ export function buildIR(sourceDir: string, viewports: number[], opts?: { motion?
       children: [],
     };
     if (raw.rawHTML) node.rawHTML = raw.rawHTML;
+    if (raw.svgPaint) node.svgPaint = raw.svgPaint;
     const srcClass = (raw.attrs?.class ?? "").trim();
     if (srcClass) node.srcClass = srcClass;
     if (Object.keys(sizingByVp).length) node.sizingByVp = sizingByVp;
@@ -346,25 +571,131 @@ export function buildIR(sourceDir: string, viewports: number[], opts?: { motion?
       const canonKids = elementChildren(raw);
       // Align this node's canonical element children to each viewport's children.
       const aligned: Record<number, (RawNode | undefined)[]> = {};
+      const kidsByVp: Record<number, RawNode[]> = {};
       for (const vw of viewports) {
         if (vw === canonical) continue;
         const m = matched[vw];
         const vwKids = m && m.tag === raw.tag ? elementChildren(m) : [];
+        kidsByVp[vw] = vwKids;
         aligned[vw] = alignChildren(canonKids, vwKids);
       }
+
+      // ---- Per-viewport DOM divergence (canonical-rooted subtrees only) ----
+      // Two inverse gaps closed here:
+      //  • GRAFT: a child that exists ONLY at non-canonical viewport(s) (destroyed/never built at
+      //    the canonical width) would otherwise never enter the IR — the clone then misses it at
+      //    the widths where the source shows it (e.g. mobile-only carousel pagination bullets).
+      //    Graft it as a sibling at its source position, carrying per-viewport data ONLY for the
+      //    viewports it appeared at; emission hides it at base and reveals it in its band(s).
+      //  • DRIFT: when a container's children at some viewport are a DIFFERENT SET on BOTH sides
+      //    (mutual whole-set mismatch — the source deterministically served other content there),
+      //    grafting would duplicate the component. Prefer faithful-at-canonical: record the drift
+      //    so emission shows the canonical children there instead of banding them all display:none
+      //    (an empty shell). Recorded in childDriftVps → doc.contentDrift → the manifest.
+      const driftVps = new Set<number>();
+      const graftsByAnchor = new Map<number, GraftGroup[]>();
+      if (matched[canonical]) {
+        for (const vw of vpsAsc) {
+          if (vw === canonical) continue;
+          const vwKids = kidsByVp[vw]!;
+          if (vwKids.length === 0) continue;
+          const matchedOther = new Set<RawNode>();
+          for (const mo of aligned[vw]!) if (mo) matchedOther.add(mo);
+          const unmatchedCanon = canonKids.filter((_, i) => !aligned[vw]![i]);
+          const unmatchedOther = vwKids.filter((k) => !matchedOther.has(k));
+          // Whole-set identity drift: many unmatched on BOTH sides, few matched, and both leftover
+          // groups are the same kind of element (same dominant tag — one component family serving
+          // different items, not a structurally different widget swapped in at this width).
+          if (
+            unmatchedCanon.length >= DRIFT_MIN_UNMATCHED &&
+            unmatchedOther.length >= DRIFT_MIN_UNMATCHED &&
+            matchedOther.size * 2 < Math.min(canonKids.length, vwKids.length) &&
+            dominantTag(unmatchedCanon) === dominantTag(unmatchedOther)
+          ) {
+            driftVps.add(vw);
+            continue; // faithful-at-canonical: do NOT graft the other set (no duplication)
+          }
+          if (unmatchedOther.length === 0 || unmatchedOther.length > GRAFT_MAX_PER_VP) continue;
+          // Graft position: each unmatched child anchors AFTER the last canonical child matched
+          // before it in this viewport's sibling order (-1 = before every canonical child).
+          const canonIdxOf = new Map<RawNode, number>();
+          aligned[vw]!.forEach((mo, i) => { if (mo) canonIdxOf.set(mo, i); });
+          let lastCanonIdx = -1;
+          const newByAnchor = new Map<number, RawNode[]>();
+          for (const k of vwKids) {
+            const ci = canonIdxOf.get(k);
+            if (ci !== undefined) { lastCanonIdx = ci; continue; }
+            let list = newByAnchor.get(lastCanonIdx);
+            if (!list) newByAnchor.set(lastCanonIdx, (list = []));
+            list.push(k);
+          }
+          // Merge this viewport's unmatched children into the anchor's existing graft groups by
+          // structural signature (the same node present at several widths becomes ONE graft with
+          // per-viewport data), preserving sibling order; leftovers open new groups in order.
+          for (const [anchor, newcomers] of [...newByAnchor.entries()].sort((a, b) => a[0] - b[0])) {
+            const groups = graftsByAnchor.get(anchor) ?? [];
+            const al = alignChildren(groups.map((g) => g.rep), newcomers);
+            const groupOfNew = new Map<RawNode, number>();
+            al.forEach((r, idx) => { if (r) groupOfNew.set(r, idx); });
+            const merged: GraftGroup[] = [];
+            let gi = 0;
+            for (const k of newcomers) {
+              const gIdx = groupOfNew.get(k);
+              if (gIdx !== undefined) {
+                while (gi <= gIdx) merged.push(groups[gi++]!);
+                groups[gIdx]!.rawByVp[vw] = k;
+              } else {
+                merged.push({ rep: k, rawByVp: { [vw]: k } });
+              }
+            }
+            while (gi < groups.length) merged.push(groups[gi++]!);
+            graftsByAnchor.set(anchor, merged);
+          }
+        }
+      }
+      // Materialize graft groups → IR nodes. Keep only groups that actually PAINT at a band
+      // viewport (a graft visible solely at a dense sample width could never be shown — bands are
+      // emitted only at the standard breakpoints — so it would be dead markup).
+      const graftedByAnchor = new Map<number, IRNode[]>();
+      for (const [anchor, groups] of [...graftsByAnchor.entries()].sort((a, b) => a[0] - b[0])) {
+        const out: IRNode[] = [];
+        for (const g of groups) {
+          const graftVps = Object.keys(g.rawByVp).map(Number).sort((a, b) => a - b);
+          if (!graftVps.some((vw) => bandVpSet.has(vw) && rawSubtreeVisible(g.rawByVp[vw]!))) continue;
+          const gm: Record<number, RawNode | undefined> = {};
+          for (const vw of viewports) gm[vw] = g.rawByVp[vw];
+          const gn = convert(g.rawByVp[graftVps[0]!]!, gm);
+          if (gn) out.push(gn);
+        }
+        if (out.length) graftedByAnchor.set(anchor, out);
+      }
+      if (driftVps.size) {
+        const bandDrift = [...driftVps].filter((v) => bandVpSet.has(v)).sort((a, b) => a - b);
+        if (bandDrift.length) node.childDriftVps = bandDrift;
+      }
+
       let ei = 0;
+      let pushedLeading = false;
+      const pushGrafts = (anchor: number): void => {
+        for (const gn of graftedByAnchor.get(anchor) ?? []) node.children.push(gn);
+      };
       for (const c of raw.children) {
         if ((c as IRTextNode).text !== undefined) {
           node.children.push({ text: (c as IRTextNode).text });
           continue;
         }
+        if (!pushedLeading) { pushGrafts(-1); pushedLeading = true; }
         const child = c as RawNode;
         const childMatched: Record<number, RawNode | undefined> = {};
-        for (const vw of viewports) childMatched[vw] = vw === canonical ? child : aligned[vw]![ei];
-        ei++;
+        // A grafted subtree has no canonical counterpart: its own children must not be treated as
+        // canonical-matched either (they carry data only at the graft's source viewports).
+        for (const vw of viewports) childMatched[vw] = vw === canonical ? (matched[canonical] ? child : undefined) : aligned[vw]![ei];
         const converted = convert(child, childMatched);
         if (converted) node.children.push(converted);
+        pushGrafts(ei);
+        ei++;
       }
+      if (!pushedLeading) pushGrafts(-1);
     }
     return node;
   };
@@ -381,6 +712,8 @@ export function buildIR(sourceDir: string, viewports: number[], opts?: { motion?
     // interactive panel so its whole (possibly display:none) subtree is retained.
     const keepAll = forced || preserveCaps.has(node.attrs["data-cid-cap"] ?? "");
     const keptChildren: IRChild[] = [];
+    // Per element child, in original order: was it kept? (for track-transform re-anchoring below.)
+    const elemKept: Array<{ child: IRNode; kept: boolean }> = [];
     let hasVisibleDescendant = false;
     let hasText = false;
     for (const c of node.children) {
@@ -397,16 +730,81 @@ export function buildIR(sourceDir: string, viewports: number[], opts?: { motion?
       if (keepAll) {
         prune(c, true);
         keptChildren.push(c);
+        elemKept.push({ child: c, kept: true });
         if (Object.values(c.visibleByVp).some(Boolean) || childHasVisible(c)) hasVisibleDescendant = true;
       } else if (prune(c, false) || keepSource) {
         keptChildren.push(c);
+        elemKept.push({ child: c, kept: true });
         if (Object.values(c.visibleByVp).some(Boolean) || childHasVisible(c)) hasVisibleDescendant = true;
+      } else {
+        elemKept.push({ child: c, kept: false });
       }
     }
     node.children = keptChildren;
+    reanchorTrackTransform(node, elemKept);
     if (keepAll) return true;
     const selfVisible = Object.values(node.visibleByVp).some(Boolean);
-    return selfVisible || hasVisibleDescendant || hasText || !!node.rawHTML;
+    return selfVisible || hasVisibleDescendant || hasText || !!node.rawHTML || isSizedInvisibleSpacer(node);
+  };
+  // An in-flow `visibility:hidden` box with a nonzero border box is LOAD-BEARING geometry: it is
+  // invisible (so `visibleByVp` is false and the visibility prune would drop it), but it still takes
+  // up its captured width/height in normal flow — a spacer/ghost column that reserves the row height
+  // its absolutely-positioned siblings paint into. Dropping it collapses the column and shifts
+  // everything below it up. Keep it as an empty sized placeholder (generation emits its w/h with
+  // `visibility:hidden` and no content). `display:none`-everywhere nodes (never in flow, zero box)
+  // and out-of-flow probes stay pruned; font-metric probes are already dropped before pruning.
+  const isSizedInvisibleSpacer = (node: IRNode): boolean => {
+    for (const vp of Object.keys(node.computedByVp).map(Number)) {
+      const cs = node.computedByVp[vp]; const bb = node.bboxByVp[vp];
+      if (!cs || !bb) continue;
+      if ((cs.display || "") === "none") continue;                    // not in flow here
+      const vis = cs.visibility || "visible";
+      if (vis !== "hidden" && vis !== "collapse") continue;           // only invisible-but-laid-out boxes
+      const pos = cs.position || "static";
+      if (pos !== "static" && pos !== "relative") continue;           // in-flow geometry only (not absolute/fixed)
+      if (bb.width > 0 && bb.height > 0) return true;                 // reserves real space
+    }
+    return false;
+  };
+  // Re-anchor a horizontally-translated TRACK container after pruning removed leading in-flow
+  // children. A settled loop carousel (Splide/Swiper/Slick) parks its track with a baked
+  // `translateX(-N)` and prepends invisible clone slides that occupy exactly [-N, 0]; the first REAL
+  // slide then paints at x=0. The visibility prune drops the off-screen clones but the baked
+  // translateX survives verbatim, so every kept slide sits N px offscreen-left (an empty band). When
+  // emission drops the leading in-flow children of such a translated track, subtract their aggregate
+  // outer width from the baked translateX per viewport so the first KEPT child lands where it was
+  // captured. NON-animated baked offsets only — animation-owned transforms are already neutralized to
+  // `none` upstream (neutralizeAnimatedTransforms), so a still-present translate here is a static bake.
+  const reanchorTrackTransform = (node: IRNode, elemKept: Array<{ child: IRNode; kept: boolean }>): void => {
+    if (elemKept.length === 0) return;
+    // Only act when a leading RUN of element children was dropped (the clone slides precede the reals).
+    const firstKeptIdx = elemKept.findIndex((e) => e.kept);
+    if (firstKeptIdx <= 0) return; // nothing dropped ahead of the first kept child (or nothing kept)
+    for (const vp of Object.keys(node.computedByVp).map(Number)) {
+      const cs = node.computedByVp[vp];
+      if (!cs || !cs.transform) continue;
+      const tx = translateXOf(cs.transform);
+      if (tx === null || tx === 0) continue; // no baked horizontal offset to re-anchor at this vp
+      // Aggregate the outer (margin-box) width of the dropped leading in-flow siblings at this vp.
+      let droppedW = 0;
+      for (let i = 0; i < firstKeptIdx; i++) {
+        const { child } = elemKept[i]!;
+        const ccs = child.computedByVp[vp]; const cb = child.bboxByVp[vp];
+        if (!ccs || !cb) continue;
+        if ((ccs.display || "") === "none") continue;
+        const cpos = ccs.position || "static";
+        if (cpos !== "static" && cpos !== "relative") continue; // out-of-flow slides don't advance the track
+        droppedW += cb.width + pfLen(ccs.marginLeft) + pfLen(ccs.marginRight);
+      }
+      if (droppedW === 0) continue;
+      // translateX is negative (track pulled left); dropping the leading clones that filled [tx, 0]
+      // means the reals shift right by droppedW → add it back. Re-anchor toward 0.
+      const next = tx + droppedW;
+      // Only re-anchor when it moves the track TOWARD the origin and doesn't overshoot past it — a
+      // guard so a partial mismatch can't push content the wrong way. Round to match capture precision.
+      if (Math.abs(next) >= Math.abs(tx)) continue;
+      cs.transform = setTranslateX(cs.transform, Math.round(next * 100) / 100);
+    }
   };
   const childHasVisible = (n: IRNode): boolean => {
     for (const c of n.children) {
@@ -427,6 +825,16 @@ export function buildIR(sourceDir: string, viewports: number[], opts?: { motion?
   };
   renumber(root);
 
+  // Content-identity drift notes (containers whose children were a different set at some band
+  // viewport — see childDriftVps). Collected AFTER renumbering so the recorded ids are final;
+  // deterministic (pre-order walk of the pruned tree).
+  const contentDrift: NonNullable<IRDoc["contentDrift"]> = [];
+  const collectDrift = (n: IRNode): void => {
+    if (n.childDriftVps?.length) contentDrift.push({ id: n.id, tag: n.tag, viewports: [...n.childDriftVps] });
+    for (const c of n.children) if (!isTextChild(c)) collectDrift(c);
+  };
+  collectDrift(root);
+
   const perViewport: IRDoc["perViewport"] = {};
   for (const vw of viewports) {
     const d = snapshots[vw]!.doc;
@@ -456,6 +864,7 @@ export function buildIR(sourceDir: string, viewports: number[], opts?: { motion?
     // benchmark + all multi-page, which don't capture motion) ⇒ none emitted, so the
     // clone stays byte-identical to the pre-Stage-5 frozen output.
     keyframes: opts?.motion ? [...new Set(canonSnap.keyframes ?? [])].sort() : [],
+    ...(contentDrift.length ? { contentDrift } : {}),
   };
 
   // Repair transient root scroll-locks. A site that locks scrolling during an intro
diff --git a/compiler/src/runner/codeAudit.ts b/compiler/src/runner/codeAudit.ts
index 5328f3f..9e66344 100644
--- a/compiler/src/runner/codeAudit.ts
+++ b/compiler/src/runner/codeAudit.ts
@@ -1,142 +1,141 @@
 /**
- * Code-quality audit — count the "bad code" tells that make a generated clone read robotic, for any
- * number of app source trees, side by side. Repeatable: point it at shipped deliverables and it
- * prints one column per tree.
+ * Code-quality audit — an honest, human-readable report over one or more generated app
+ * trees. Built directly on the dimension scorer in ./qualityScore, so the audit and the
+ * shipped `code-quality.md` quality number never disagree.
  *
- *   npm run audit                                  # auto: every output/<site>/app
- *   npm run audit -- <dir> [<dir> ...]             # explicit trees; .clone resolves to sibling app/
- *   npm run audit -- output/example/app
+ *   npm run audit                                  # auto: every runs/<site>/latest/generated/app
+ *   npm run audit -- <appDir> [<appDir> ...]       # explicit app trees
+ *   npm run audit -- runs/example/latest/generated/app
+ *   npm run audit -- <dir> --json                  # machine-readable
  *
- * Scans .tsx/.jsx/.ts/.css under each dir (skips node_modules/.next/out/dotfiles). Every metric is a
- * COUNT where lower is better, except the two "good" context rows (fluid width / standard scale).
- * The decisive "decimal" tell is non-integer-PX: each arbitrary px/rem is converted to px and flagged
- * if it isn't a whole pixel (a frozen measurement), so a clean 12.5rem (=200px) does NOT count.
+ * For each tree it prints:
+ *   • the LETTER GRADE + numeric score (and any hard-cap reason),
+ *   • a per-DIMENSION table (payload / decomposition / duplication / semantics / hygiene
+ *     / runtime) with the visible sub-metrics behind each score,
+ *   • the TOP OFFENDERS (file, metric, value) — the worst individual tells.
+ * When several trees are passed it also prints a side-by-side grade comparison.
+ *
+ * Pure static analysis over generated source (.tsx/.jsx/.ts/.astro/.css). No builds, no
+ * browser. See qualityScore.ts for the rubric + the (calibration-guide) thresholds.
  */
-import { readdirSync, statSync, readFileSync, existsSync } from "node:fs";
-import { join, resolve, basename, dirname, sep } from "node:path";
+import { readdirSync, statSync, existsSync } from "node:fs";
+import { join, resolve, basename } from "node:path";
+import { scoreApp, type QualityReport } from "./qualityScore.js";
 
-type Row = { label: string; lowerBetter: boolean; values: number[] };
-type Target = { inputDir: string; scanDir: string; validationDir?: string };
+// ---------------------------------------------------------------------------
+// Target resolution — accept an app dir directly, or discover deliverables.
+// ---------------------------------------------------------------------------
 
-function readTree(dir: string): { tsx: string; css: string; all: string } {
-  const tsxParts: string[] = [], cssParts: string[] = [];
-  const walk = (d: string): void => {
-    for (const n of readdirSync(d)) {
-      if (n === "node_modules" || n === ".next" || n === "out" || n.startsWith(".")) continue;
-      const p = join(d, n);
-      const st = statSync(p);
-      if (st.isDirectory()) walk(p);
-      else if (/\.(tsx|jsx|ts)$/.test(n)) tsxParts.push(readFileSync(p, "utf8"));
-      else if (/\.css$/.test(n)) cssParts.push(readFileSync(p, "utf8"));
+/** Is `dir` a scannable app tree (has a src/ with code in it, or is itself full of code)? */
+function isAppDir(dir: string): boolean {
+  if (!existsSync(dir)) return false;
+  if (existsSync(join(dir, "src"))) return true;
+  try { return readdirSync(dir).some((n) => /\.(tsx|jsx|ts|css|astro)$/.test(n)); } catch { return false; }
+}
+
+/** Discover every runs/<site>/latest/generated/app deliverable, newest layout first.
+ *  Checks both the cwd and its parent, so `npm run audit` works whether invoked from the
+ *  repo root or from compiler/ (where runs/ lives one level up). */
+function discoverTargets(): string[] {
+  const out: string[] = [];
+  const roots = ["runs", "output", "../runs", "../output"].map((r) => resolve(r)).filter(existsSync);
+  for (const root of roots) {
+    let sites: string[];
+    try { sites = readdirSync(root); } catch { continue; }
+    for (const site of sites) {
+      for (const app of [
+        join(root, site, "latest", "generated", "app"),
+        join(root, site, "app"),
+      ]) {
+        if (isAppDir(app)) { out.push(app); break; }
+      }
     }
-  };
-  walk(dir);
-  const tsx = tsxParts.join("\n"), css = cssParts.join("\n");
-  return { tsx, css, all: tsx + "\n" + css };
+  }
+  return out;
 }
 
-/** All metric counts for one tree. */
-function audit(target: Target): Record<string, number> {
-  const dir = target.scanDir;
-  const { tsx, css, all } = readTree(dir);
-  const n = (re: RegExp, s = all): number => (s.match(re) || []).length;
-  const validationDataCid = target.validationDir && existsSync(target.validationDir)
-    ? (readTree(target.validationDir).all.match(/data-cid/g) || []).length
-    : 0;
+// ---------------------------------------------------------------------------
+// Rendering
+// ---------------------------------------------------------------------------
 
-  // Arbitrary px/rem values + the non-integer-px ("decimal") subset, the decisive measurement tell.
-  let arb = 0, decimal = 0;
-  for (const m of all.matchAll(/\[(-?[0-9]+\.?[0-9]*)(px|rem)\]/g)) {
-    arb++;
-    const px = parseFloat(m[1]!) * (m[2] === "rem" ? 16 : 1);
-    if (Math.abs(px - Math.round(px)) > 0.02) decimal++;
-  }
-
-  return {
-    "files (tsx+css)": (tsx ? 1 : 0), // overwritten below with real file counts
-    "── BAD (lower=better) ──": -1,
-    "fixed width  w-[Npx/rem]": n(/\bw-\[-?[0-9.]+(?:px|rem)\]/g),
-    "fixed height h-[Npx/rem]": n(/\bh-\[-?[0-9.]+(?:px|rem)\]/g),
-    "breakpoint utilities": n(/\b(?:sm|md|lg|xl|2xl|max-sm|max-md|max-lg|max-xl):/g),
-    "arbitrary bands min/max-[Npx]:": n(/\b(?:min|max)-\[[0-9]+px\]:/g),
-    "arbitrary […px/rem] total": arb,
-    "decimal (non-integer px)": decimal,
-    "baked position top/left/inset-[N]": n(/\b(?:top|left|right|bottom|inset(?:-x|-y)?)-\[-?[0-9.]+(?:px|rem)\]/g),
-    "raw color literal [#hex/rgb]": n(/\[(?:#[0-9a-fA-F]{3,8}|rgba?\([^\]]*)\]/g),
-    "per-side border longhand": n(/\[border-(?:top|right|bottom|left)-(?:style|color):/g),
-    "data-cid (shipped)": n(/data-cid/g),
-    "data-cid (validation-only)": validationDataCid,
-    "dangerouslySetInnerHTML": n(/dangerouslySetInnerHTML/g),
-    "': any' props": n(/:\s*any\b/g),
-    "robotic 'Generated by' comments": n(/Generated by clone|clone-static/g),
-    "── GOOD (higher=better) ──": -1,
-    "fluid width (w-full/auto/fraction)": n(/\bw-(?:full|auto|fit|screen|\d{1,2}\/\d{1,2})\b/g),
-    "standard scale (gap-2/w-10/p-4…)": n(/\b(?:gap|p|px|py|pt|pb|pl|pr|m|mx|my|mt|mb|w|h)-(?:0|0\.5|1|1\.5|2|2\.5|3|3\.5|4|5|6|7|8|9|10|11|12|14|16|20|24|28|32|36|40|44|48|52|56|60|64|72|80|96|px)\b/g),
-  };
+/** A readable column label for a target (its site/run name where possible). */
+function labelFor(dir: string): string {
+  const parts = resolve(dir).split("/");
+  const runsIdx = parts.lastIndexOf("runs");
+  const outIdx = parts.lastIndexOf("output");
+  const i = runsIdx >= 0 ? runsIdx : outIdx;
+  if (i >= 0 && parts[i + 1]) return parts[i + 1]!.slice(0, 22);
+  return (parts[parts.length - 2] ?? basename(dir)).slice(0, 22);
 }
 
-function fileCount(dir: string): number {
-  let c = 0;
-  const walk = (d: string): void => { for (const x of readdirSync(d)) { if (x === "node_modules" || x === ".next" || x === "out" || x.startsWith(".")) continue; const p = join(d, x); statSync(p).isDirectory() ? walk(p) : (/\.(tsx|jsx|ts|css)$/.test(x) && c++); } };
-  walk(dir);
-  return c;
+const pad = (s: string, w: number): string => s + " ".repeat(Math.max(0, w - s.length));
+const padL = (s: string, w: number): string => " ".repeat(Math.max(0, w - s.length)) + s;
+
+function renderReport(label: string, rep: QualityReport): string {
+  const L: string[] = [];
+  L.push("");
+  L.push(`━━━ ${label} ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━`);
+  L.push(`  GRADE ${rep.grade}   (${rep.total}/100)`);
+  if (rep.caps.length) {
+    L.push(`  HARD CAP → grade limited to D-range:`);
+    for (const c of rep.caps) L.push(`    • ${c}`);
+  }
+  L.push("");
+  L.push(`  ${pad("dimension", 15)}${padL("score", 9)}   sub-metrics`);
+  L.push(`  ${"─".repeat(66)}`);
+  for (const [dim, cat] of Object.entries(rep.categories)) {
+    const metrics = Object.entries(cat.metrics).map(([k, v]) => `${k}=${v}`).join(" ");
+    L.push(`  ${pad(dim, 15)}${padL(`${cat.score}/${cat.max}`, 9)}   ${metrics}`);
+  }
+  if (rep.offenders.length) {
+    L.push("");
+    L.push(`  top offenders`);
+    L.push(`  ${pad("metric", 34)}${padL("value", 12)}  file`);
+    L.push(`  ${"─".repeat(66)}`);
+    for (const o of rep.offenders.slice(0, 10)) {
+      L.push(`  ${pad(o.metric, 34)}${padL(String(o.value), 12)}  ${o.file}`);
+    }
+  }
+  return L.join("\n");
 }
 
-function normalizeTarget(input: string): Target {
-  const d = resolve(input);
-  const asApp = (appDir: string, validationDir?: string): Target => ({ inputDir: d, scanDir: appDir, validationDir });
-  if (basename(d) === ".clone") {
-    const app = join(dirname(d), "app");
-    const validation = join(d, "generated", "app");
-    if (existsSync(join(app, "src"))) return asApp(app, existsSync(validation) ? validation : undefined);
+function renderComparison(labels: string[], reps: QualityReport[]): string {
+  const L: string[] = [];
+  const colW = Math.max(12, ...labels.map((l) => l.length + 2));
+  L.push("");
+  L.push(`━━━ comparison ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━`);
+  L.push("  " + pad("dimension", 15) + labels.map((l) => padL(l, colW)).join(""));
+  const dims = Object.keys(reps[0]!.categories);
+  for (const d of dims) {
+    L.push("  " + pad(d, 15) + reps.map((r) => padL(String(r.categories[d]!.score), colW)).join(""));
   }
-  const generatedSuffix = `${sep}.clone${sep}generated${sep}app`;
-  if (d.endsWith(generatedSuffix)) {
-    const cloneDir = d.slice(0, -`${sep}generated${sep}app`.length);
-    const app = join(dirname(cloneDir), "app");
-    if (existsSync(join(app, "src"))) return asApp(app, d);
-  }
-  if (basename(d) === "generated" && existsSync(join(d, "app", "src"))) {
-    const cloneDir = dirname(d);
-    const app = join(dirname(cloneDir), "app");
-    if (basename(cloneDir) === ".clone" && existsSync(join(app, "src"))) return asApp(app, join(d, "app"));
-  }
-  return { inputDir: d, scanDir: d };
+  L.push("  " + pad("GRADE", 15) + reps.map((r) => padL(`${r.grade} (${r.total})`, colW)).join(""));
+  return L.join("\n");
 }
 
+// ---------------------------------------------------------------------------
+// Main
+// ---------------------------------------------------------------------------
+
 function main(): void {
   const args = process.argv.slice(2).filter((a) => !a.startsWith("--"));
-  let targets: Target[];
-  if (args.length) targets = args.map(normalizeTarget);
-  else {
-    // Auto: every output/<site>/app deliverable.
-    const outRoot = resolve("output");
-    const sites = existsSync(outRoot)
-      ? readdirSync(outRoot).map((s) => join(outRoot, s, "app")).filter((p) => existsSync(join(p, "src")))
-      : [];
-    targets = sites.map(normalizeTarget);
-  }
-  targets = targets.filter((t) => existsSync(t.scanDir));
-  if (!targets.length) { console.error("no app trees found — pass dirs explicitly"); process.exit(1); }
+  const asJson = process.argv.includes("--json");
+  const targets = (args.length ? args.map((a) => resolve(a)) : discoverTargets()).filter(isAppDir);
+  if (!targets.length) { console.error("no app trees found — pass app dirs explicitly (e.g. runs/<site>/latest/generated/app)"); process.exit(1); }
 
-  // A readable column label: the deliverable dir's parent name, or the scanned dir name.
-  const label = (t: Target): string => (basename(dirname(t.scanDir)) || basename(t.scanDir)).slice(0, 16);
-  const labels = targets.map(label);
-  const audits = targets.map(audit);
-  audits.forEach((a, i) => { a["files (tsx+css)"] = fileCount(targets[i]!.scanDir); });
+  const labels = targets.map(labelFor);
+  const reports = targets.map((t) => scoreApp(t));
 
-  const keys = Object.keys(audits[0]!);
-  const w0 = Math.max(...keys.map((k) => k.length));
-  const colW = Math.max(11, ...labels.map((l) => l.length));
-  const pad = (s: string, w: number) => s + " ".repeat(Math.max(0, w - s.length));
-  console.log("\n" + pad("metric", w0) + "  " + labels.map((l) => pad(l, colW)).join(""));
-  console.log("─".repeat(w0 + 2 + colW * labels.length));
-  for (const k of keys) {
-    if (audits[0]![k] === -1) { console.log(pad(k, w0)); continue; } // section header
-    const cells = audits.map((a) => pad(String(a[k] ?? 0), colW)).join("");
-    console.log(pad(k, w0) + "  " + cells);
+  if (asJson) {
+    console.log(JSON.stringify(reports.map((r, i) => ({ label: labels[i], ...r })), null, 2));
+    return;
   }
-  console.log("\n(counts; lower is better in the BAD block, higher in the GOOD block. 'decimal' = the\n arbitrary value's px isn't a whole pixel — the frozen-measurement tell.)\n");
+
+  for (let i = 0; i < reports.length; i++) console.log(renderReport(labels[i]!, reports[i]!));
+  if (reports.length > 1) console.log(renderComparison(labels, reports));
+  console.log("\n(scores are out of each dimension's max; grade is the weighted blend, capped to\n D-range if any single file/line/blob is in catastrophic payload territory.)\n");
 }
 
-main();
+if (import.meta.url === `file://${process.argv[1]}`) {
+  main();
+}
diff --git a/compiler/src/runner/qualityScore.ts b/compiler/src/runner/qualityScore.ts
index 8ff0d7c..dea52c2 100644
--- a/compiler/src/runner/qualityScore.ts
+++ b/compiler/src/runner/qualityScore.ts
@@ -1,23 +1,93 @@
 /**
- * Output-quality rubric (deterministic, framework-agnostic).
+ * Output-quality rubric — HONEST edition (deterministic, framework-agnostic).
  *
  * The fidelity gates (validate/gates.ts) measure whether the clone *looks and
  * behaves* like the source. They say nothing about whether the generated CODE is
- * good — componentized, semantically named, styled through a reusable token/class
- * system, editable, and well organized. That "developer-facing quality" is exactly
- * where a deterministic converter is judged once fidelity is a given.
+ * good — small files, decomposed into real components, semantic and accessible,
+ * free of capture artifacts, and safe at runtime. That "developer-facing quality"
+ * is what a deterministic converter is judged on once fidelity is a given.
  *
- * This module statically analyzes a generated app directory and scores it 0–100 on
- * six categories. It reads only source text (`.tsx/.jsx/.ts/.astro/.css`). The
- * metrics are chosen to be framework-agnostic: e.g. "style reuse" rewards shared
- * classes whether they're Tailwind utilities or semantic clone classes, and
- * penalizes per-node unique rules (`.c1{...} .c2{...}`) regardless of framework.
+ * This module statically analyzes a generated app directory (source text only —
+ * `.tsx/.jsx/.ts/.astro/.css`) and scores it 0–100 across SIX dimensions, each
+ * with visible subscores. The score is a weighted blend of the dimensions EXCEPT
+ * that a single dimension in catastrophic territory (a multi-megabyte source file,
+ * a 100KB+ single line) HARD-CAPS the overall grade into D-range no matter how
+ * clean everything else is — because such a file is unopenable, un-diffable, and
+ * un-editable, which is the whole point of "good code".
+ *
+ * The signals are deliberately general (payload bytes, LOC distribution, repeated
+ * definitions, semantic-tag ratios, whitespace/capture artifacts, uncleaned
+ * listeners) so the scorer is not tuned to any specific site — it measures the
+ * failure *modes* a robotic converter falls into, not any one output.
  *
  * Pure + deterministic: same directory ⇒ same score.
  */
 import { readFileSync, readdirSync, statSync } from "node:fs";
 import { join, extname, basename, relative } from "node:path";
 
+// ===========================================================================
+// CALIBRATION CONSTANTS
+// ---------------------------------------------------------------------------
+// These are CALIBRATION GUIDES, expected to be tuned as the generator and our
+// taste evolve — they are NOT compliance targets or contractual thresholds. A
+// number here answers "where does a human reviewer start wincing?", set from
+// observed good vs. bad outputs, and should be re-fit (not litigated) whenever
+// calibration drifts. Every knob lives in this one block on purpose.
+// ===========================================================================
+const K = {
+  // ---- payload discipline (a file/line so big it is not human-readable) ----
+  FILE_BYTES_GOOD: 30_000, // ≤30KB source file: comfortable to open
+  FILE_BYTES_BAD: 160_000, // ≥160KB: a reviewer scrolls forever; scores ~0
+  LINE_CHARS_GOOD: 2_000, // a formatted line, allowing for a dense data/JSX row
+  LINE_CHARS_BAD: 30_000, // a giant one-liner (minified / HTML-as-string prop)
+  INLINE_BYTES_GOOD: 50_000, // total base64 / inline-HTML bytes that's forgivable
+  INLINE_BYTES_BAD: 2_000_000, // 2MB+ of embedded blobs: catastrophic payload
+  // Catastrophe caps: any ONE of these forces the whole app into D-range.
+  CATASTROPHE_FILE_BYTES: 1_000_000, // a >1MB source file
+  CATASTROPHE_LINE_CHARS: 100_000, // a >100KB single line
+  CATASTROPHE_INLINE_BYTES: 5_000_000, // >5MB of embedded base64/HTML
+  CAP_GRADE_D: 68, // ceiling applied when a catastrophe fires — top of the D band, so a
+  //   catastrophic payload can grade no better than D+ regardless of other dimensions
+  // Softer cap for "very bad but not unopenable" payloads.
+  WARN_FILE_BYTES: 350_000,
+  WARN_LINE_CHARS: 40_000,
+  CAP_GRADE_C: 78, // ceiling for the softer warning band (top of C+)
+
+  // ---- component decomposition (is the page a monolith?) ----
+  MONOLITH_DOMINANCE_GOOD: 0.3, // biggest file ≤30% of all tags → well spread
+  MONOLITH_DOMINANCE_BAD: 0.75, // one file holds ≥75% of the page → monolith
+  BIG_SECTION_LINES: 600, // a "section" this long is really a whole page
+  COMPONENTS_GOOD: 12, // this many real components → full decomposition credit
+
+  // ---- duplication ----
+  DUP_HELPER_RATIO_BAD: 0.4, // ≥40% of helper defs are copy-paste duplicates
+  DUP_SVG_PATH_RATIO_BAD: 0.85, // ≥85% of inline <path> strings are repeats (shared
+  //   icon sets legitimately repeat, so only near-total duplication is a real tell)
+  NEAR_DUP_COMPONENT_BAD: 14, // this many near-identical NON-trivial component pairs → 0
+  NEAR_DUP_MIN_TAGS: 8, // ignore tiny components (icons/logos) in near-dup detection
+
+  // ---- semantics / a11y ----
+  DIV_RATIO_GOOD: 0.6, // ≤60% of elements are bare div/span → healthy
+  DIV_RATIO_BAD: 0.9, // ≥90% divs → div soup
+  ALT_COVERAGE_GOOD: 0.9, // ≥90% of <img> carry alt=
+  H1_REQUIRED: 1, // a page really should have exactly one <h1>
+
+  // ---- hygiene ----
+  // {" "} literals and sub-pixel arbitraries are a KNOWN baseline quirk of this
+  // converter present in even good output — only pathological volumes should bite,
+  // so these BADs sit well above what a "decent" tree emits.
+  WS_LITERAL_PER_KTAG_GOOD: 100, // per 1000 tags a converter routinely emits some
+  WS_LITERAL_PER_KTAG_BAD: 1200, // this many → capture-whitespace noise dominates
+  SUBPIXEL_PER_KTAG_GOOD: 60, // some frozen measurements are unavoidable
+  SUBPIXEL_PER_KTAG_BAD: 260, // a wall of frozen sub-pixels → machine replay
+  OPAQUE_TOKEN_RATIO_BAD: 0.6, // ≥60% of CSS custom props are opaque --clr-N / hashes
+  PROBE_ARTIFACTS_BAD: 8, // off-screen capture-probe text leaks
+
+  // ---- runtime discipline ----
+  LEAK_LISTENERS_GOOD: 8, // a small shared runtime bundle carries a few listeners
+  LEAK_LISTENERS_BAD: 30, // this many uncleaned adds → real leak territory
+} as const;
+
 // ---------------------------------------------------------------------------
 // File collection
 // ---------------------------------------------------------------------------
@@ -51,13 +121,43 @@ export function collectFiles(root: string): SrcFile[] {
 }
 
 // ---------------------------------------------------------------------------
-// Primitive extraction
+// Small helpers
+// ---------------------------------------------------------------------------
+
+const clamp01 = (x: number): number => Math.max(0, Math.min(1, x));
+/** Linear ramp: v in [lo,hi] → [0,1]. Handles lo>hi (descending / "lower is better"). */
+function ramp(v: number, lo: number, hi: number): number {
+  if (lo === hi) return v >= hi ? 1 : 0;
+  return clamp01((v - lo) / (hi - lo));
+}
+/** A value where HIGHER is worse: good at `good`, zero at `bad`. */
+const penalize = (v: number, good: number, bad: number): number => 1 - ramp(v, good, bad);
+const r1 = (n: number): number => Math.round(n * 10) / 10;
+
+/** Longest single line (in chars) in a file. */
+function maxLineLen(text: string): number {
+  let max = 0, start = 0;
+  for (let i = 0; i < text.length; i++) {
+    if (text.charCodeAt(i) === 10) { if (i - start > max) max = i - start; start = i + 1; }
+  }
+  if (text.length - start > max) max = text.length - start;
+  return max;
+}
+
+/** Count JSX/HTML opening element tags — a framework-agnostic page-size proxy. */
+function countTags(text: string): number {
+  const m = text.match(/<[a-zA-Z][a-zA-Z0-9.]*(\s|\/|>)/g);
+  return m ? m.length : 0;
+}
+
+// ---------------------------------------------------------------------------
+// Structural classification
 // ---------------------------------------------------------------------------
 
 const CONFIG_NAME_RE = /(config|tsconfig|next-env|site-config|content\.config|\.config\.)/i;
 const ROOT_NAME_RE = /(^|\/)(layout|_app|_document|root-layout)\.[jt]sx$/i;
-/** Files that compose the whole page (the "entry"): page.tsx (Next), index/page in a
- *  pages/ dir, home.tsx, or an .astro route shell. Used for the dominance metric. */
+const SECTION_WORDS = ["hero", "footer", "navbar", "nav", "header", "about", "cta", "feature", "pricing", "faq", "logo", "logocloud", "testimonial", "gallery", "stories", "spotlight", "knowledge", "news", "apply", "contact", "banner", "team", "stats", "partners", "alumni", "founder", "section"];
+
 function isEntryFile(rel: string): boolean {
   const b = basename(rel).toLowerCase();
   if (/^(page|index|home|app)\.[jt]sx$/.test(b)) return true;
@@ -66,54 +166,8 @@ function isEntryFile(rel: string): boolean {
   return false;
 }
 
-const SECTION_WORDS = ["hero", "footer", "navbar", "nav", "header", "about", "cta", "feature", "pricing", "faq", "logo", "logocloud", "testimonial", "gallery", "stories", "spotlight", "knowledge", "news", "apply", "contact", "banner", "team", "stats", "partners", "alumni", "founder", "section"];
-
-/** Count JSX/HTML opening element tags — a framework-agnostic proxy for page size
- *  (how many DOM nodes the output describes). Excludes React fragments + closing tags. */
-function countTags(text: string): number {
-  const m = text.match(/<[a-zA-Z][a-zA-Z0-9.]*(\s|\/|>)/g);
-  return m ? m.length : 0;
-}
-
-/** All className / class string-literal tokens used on elements (space split).
- *  Catches JSX attribute form (className="…"), object/spread form (className: "…" —
- *  what our generator emits), and hoisted className consts. A dynamic per-node class
- *  (className: "c" + d._cid / className={"c"+…}) renders a UNIQUE opaque class per
- *  instance, so each occurrence is recorded as its own opaque token (keeping the
- *  reuse + semantic metrics honest for the per-node-CSS strategy). */
-function classTokens(text: string): string[] {
-  const out: string[] = [];
-  // className="..."  /  className: "..."  /  "class": "..."  (attr + object form)
-  const re = /\b(?:className|class)\s*(?:=|:)\s*"([^"]*)"/g;
-  let m: RegExpExecArray | null;
-  while ((m = re.exec(text)) !== null) {
-    for (const t of m[1]!.split(/\s+/)) if (t) out.push(t);
-  }
-  // hoisted className consts: const xClassName = "..."
-  const re2 = /\b(?:const|let)\s+\w*[Cc]lassName\w*\s*=\s*"([^"]*)"/g;
-  while ((m = re2.exec(text)) !== null) {
-    for (const t of m[1]!.split(/\s+/)) if (t) out.push(t);
-  }
-  // dynamic per-node class: className: "c" + d._cid  /  className={"c"+ ...}
-  const dyn = (text.match(/\bclassName\s*(?:=\s*\{|:)\s*"c[a-z]?"\s*\+/g) ?? []).length
-    + (text.match(/\bclassName\s*(?:=\s*\{|:)\s*"c[a-z]?\d*"\s*\+/g) ?? []).length;
-  for (let i = 0; i < dyn; i++) out.push(`c__dyn${out.length}`); // unique opaque per occurrence
-  return out;
-}
-
-const CID_CLASS_RE = /^c[a-z]?\d+$/; // our legacy per-node class: c12 / cn12
-/** A class token that carries no human meaning (pure id / hash). */
-function isOpaqueClass(t: string): boolean {
-  if (CID_CLASS_RE.test(t)) return true;
-  if (/^[a-z]?\d+$/.test(t)) return true;
-  // hashed CSS-module-ish tokens: _foo_ab12 or 6-hex tails
-  if (/_[a-z0-9]{5,}$/i.test(t) && /\d/.test(t)) return true;
-  return false;
-}
-
 const GENERIC_COMP_RE = /^(Item|Card|List|ListItem|Link|LinkItem|Wrapper|Box|Div|El|Node|Group|Block|Comp|Component|Row|Col|Cell|Thing|Unit|Part|Chunk)\d*$/;
-/** Exported / defined component names in a file. */
-function componentNames(text: string): string[] {
+export function componentNames(text: string): string[] {
   const names = new Set<string>();
   let m: RegExpExecArray | null;
   const re1 = /export\s+default\s+function\s+([A-Z]\w*)/g;
@@ -125,221 +179,428 @@ function componentNames(text: string): string[] {
   return [...names];
 }
 
-/** Data/content field names declared in a content or data module. */
-function contentFieldNames(text: string): string[] {
-  const out: string[] = [];
-  // type Foo = { a: string; b?: number } — capture keys
-  const typeBlocks = text.match(/(?:type|interface)\s+\w+\s*=?\s*\{([^}]*)\}/g) ?? [];
-  for (const blk of typeBlocks) {
-    const re = /(\w+)\s*\??\s*:/g; let m: RegExpExecArray | null;
-    while ((m = re.exec(blk)) !== null) out.push(m[1]!);
+// ===========================================================================
+// METRIC EXTRACTORS  (exported for unit tests — each is a pure text→number/obj)
+// ===========================================================================
+
+/** Bytes of embedded base64 blobs + HTML passed as string props/dangerous html. */
+export function inlineBlobBytes(text: string): number {
+  let bytes = 0;
+  // base64 data URIs — the payload after the comma.
+  for (const m of text.matchAll(/data:[^;,'"`)\s]*;base64,([A-Za-z0-9+/=]+)/g)) bytes += m[1]!.length;
+  // dangerouslySetInnerHTML / html-string props: a big string literal handed to markup.
+  for (const m of text.matchAll(/dangerouslySetInnerHTML/g)) void m;
+  // A very long string literal that is actually markup ("<div ...</div>" as a prop).
+  for (const m of text.matchAll(/"((?:[^"\\]|\\.){2000,})"/g)) {
+    const s = m[1]!;
+    if (/<[a-z][a-z0-9]*[\s>]/i.test(s) && (s.match(/</g)?.length ?? 0) > 20) bytes += s.length;
   }
-  return out;
+  return bytes;
+}
+
+/** Payload facts about one file. */
+export function filePayload(f: SrcFile): { bytes: number; maxLine: number; inlineBytes: number } {
+  return { bytes: f.text.length, maxLine: maxLineLen(f.text), inlineBytes: inlineBlobBytes(f.text) };
+}
+
+/** {" "} / {' '} whitespace-only JSX expression literals (a capture artifact). */
+export function whitespaceLiterals(text: string): number {
+  return (text.match(/\{\s*["'`]\s+["'`]\s*\}/g) ?? []).length
+    + (text.match(/\{["'`]\\u00a0["'`]\}/gi) ?? []).length;
+}
+
+/** Frozen sub-pixel arbitrary values: `[12.5px]`, `w-[713.938px]` where px isn't whole. */
+export function subpixelArbitraries(text: string): number {
+  let n = 0;
+  for (const m of text.matchAll(/\[(-?[0-9]+\.?[0-9]*)(px|rem)\]/g)) {
+    const px = parseFloat(m[1]!) * (m[2] === "rem" ? 16 : 1);
+    if (Math.abs(px - Math.round(px)) > 0.02) n++;
+  }
+  return n;
+}
+
+/** CSS custom-property definitions split into opaque (--clr-7, --c12, hashes) vs named. */
+export function customPropTokens(text: string): { total: number; opaque: number } {
+  let total = 0, opaque = 0;
+  for (const m of text.matchAll(/(^|[^\w-])(--[\w-]+)\s*:/g)) {
+    const name = m[2]!.slice(2); // strip leading --
+    total++;
+    if (/^(clr|c|color|var|token|t|v|n|x)?-?\d+$/i.test(name) || /^[a-f0-9]{6,}$/i.test(name)) opaque++;
+  }
+  return { total, opaque };
+}
+
+/** Off-screen capture-probe text leaks (measurement scaffolding shipped into markup):
+ *  probe data-attrs, __probe__ markers, and clip:rect(0…) off-screen clipping. */
+export function probeArtifacts(text: string): number {
+  return (text.match(/(?:data-(?:probe|measure|ditto-probe)|__probe__|offscreen-probe|clip:\s*["'`]?\s*rect\(\s*0)/g) ?? []).length;
+}
+
+/** addEventListener calls with no matching removeEventListener / cleanup return. */
+export function uncleanedListeners(text: string): number {
+  const adds = (text.match(/\.addEventListener\s*\(/g) ?? []).length;
+  const removes = (text.match(/\.removeEventListener\s*\(/g) ?? []).length;
+  // A cleanup return (useEffect teardown / AbortController) neutralizes some adds.
+  const hasCleanupReturn = /return\s*\(\s*\)\s*=>/.test(text) || /new AbortController/.test(text) || /\{\s*signal\s*\}/.test(text);
+  const covered = hasCleanupReturn ? Math.max(removes, adds) : removes;
+  return Math.max(0, adds - covered);
+}
+
+/** Element-tag histogram for a whole tree of markup text. */
+export function tagHistogram(text: string): Record<string, number> {
+  const h: Record<string, number> = {};
+  for (const m of text.matchAll(/<([a-z][a-z0-9]*)(?:\s|\/|>)/g)) {
+    const t = m[1]!;
+    h[t] = (h[t] ?? 0) + 1;
+  }
+  return h;
+}
+
+/** aria-hidden applied to a focusable/interactive element in the same tag. */
+export function ariaHiddenFocusables(text: string): number {
+  let n = 0;
+  for (const m of text.matchAll(/<(a|button|input|select|textarea)\b[^>]*aria-hidden\s*=\s*["'{]?\s*true/gi)) void m;
+  n += (text.match(/<(?:a|button|input|select|textarea)\b[^>]*aria-hidden\s*=\s*["'{]?\s*true/gi) ?? []).length;
+  return n;
+}
+
+/** Repeated helper/function definitions with identical bodies (copy-paste, not shared). */
+export function duplicateHelpers(text: string): { defs: number; dups: number } {
+  const bodies = new Map<string, number>();
+  // named function / arrow-const helper definitions with a brace body.
+  const re = /(?:function\s+\w+\s*\([^)]*\)|const\s+\w+\s*=\s*(?:\([^)]*\)|\w+)\s*=>)\s*\{([\s\S]{40,600}?)\}/g;
+  let m: RegExpExecArray | null;
+  let defs = 0;
+  while ((m = re.exec(text)) !== null) {
+    defs++;
+    const key = m[1]!.replace(/\s+/g, " ").trim();
+    bodies.set(key, (bodies.get(key) ?? 0) + 1);
+  }
+  let dups = 0;
+  for (const c of bodies.values()) if (c > 1) dups += c - 1;
+  return { defs, dups };
+}
+
+/** Inline SVG <path d="…"> strings, and how many are exact repeats. */
+export function svgPathDuplication(text: string): { total: number; repeats: number } {
+  const seen = new Map<string, number>();
+  let total = 0;
+  for (const m of text.matchAll(/\bd\s*=\s*["']([Mm][^"']{20,})["']/g)) {
+    total++;
+    const key = m[1]!;
+    seen.set(key, (seen.get(key) ?? 0) + 1);
+  }
+  let repeats = 0;
+  for (const c of seen.values()) if (c > 1) repeats += c - 1;
+  return { total, repeats };
+}
+
+/** Near-identical component pairs: same tag-histogram signature across component files. */
+export function nearDuplicateComponents(sigs: string[]): number {
+  const counts = new Map<string, number>();
+  for (const s of sigs) counts.set(s, (counts.get(s) ?? 0) + 1);
+  let pairs = 0;
+  for (const c of counts.values()) if (c > 1) pairs += c - 1;
+  return pairs;
 }
-const PLUMBING_FIELD_RE = /^(_cid\d*|cid\d*|value\d*|val\d*|f\d+|d\d+|field\d+|key\d*|prop\d+|arg\d+)$/;
 
 // ---------------------------------------------------------------------------
-// Scoring
+// Grading
 // ---------------------------------------------------------------------------
 
+export type LetterGrade = "A" | "A-" | "B+" | "B" | "B-" | "C+" | "C" | "C-" | "D+" | "D" | "D-" | "F";
+export function toLetter(total: number): LetterGrade {
+  if (total >= 93) return "A";
+  if (total >= 90) return "A-";
+  if (total >= 87) return "B+";
+  if (total >= 83) return "B";
+  if (total >= 80) return "B-";
+  if (total >= 77) return "C+";
+  if (total >= 73) return "C";
+  if (total >= 70) return "C-";
+  if (total >= 66) return "D+";
+  if (total >= 63) return "D";
+  if (total >= 60) return "D-";
+  return "F";
+}
+
 export type CategoryScore = { score: number; max: number; metrics: Record<string, number | string> };
+export type Offender = { file: string; metric: string; value: number };
 export type QualityReport = {
   dir: string;
   total: number;
+  grade: LetterGrade;
+  caps: string[];
   categories: Record<string, CategoryScore>;
+  offenders: Offender[];
   raw: Record<string, number>;
 };
 
-const clamp01 = (x: number): number => Math.max(0, Math.min(1, x));
-/** Linear ramp: value v mapped from [lo,hi] → [0,1]. */
-const ramp = (v: number, lo: number, hi: number): number => clamp01((v - lo) / (hi - lo));
-const r1 = (n: number): number => Math.round(n * 10) / 10;
+/** Dimension weights (sum = 100). Guiding, not exact — see CALIBRATION note.
+ *  Payload + decomposition carry the most weight because an unopenable, monolithic
+ *  file is the defect a reviewer notices first; hygiene/duplication are lighter
+ *  because this converter's baseline (some {" "}, shared icons) is tolerable. */
+const WEIGHTS = {
+  payload: 26,
+  decomposition: 18,
+  duplication: 12,
+  semantics: 18,
+  hygiene: 14,
+  runtime: 12,
+} as const;
 
 export function scoreApp(root: string): QualityReport {
   const files = collectFiles(root);
-  const tsx = files.filter((f) => f.ext === ".tsx" || f.ext === ".jsx" || f.ext === ".astro");
+  const markup = files.filter((f) => f.ext === ".tsx" || f.ext === ".jsx" || f.ext === ".astro");
   const css = files.filter((f) => f.ext === ".css");
+  const runtimeFiles = files.filter((f) => f.ext === ".ts" || f.ext === ".tsx" || f.ext === ".jsx");
 
-  // Component modules = JSX-bearing files that aren't config/root-layout.
-  const componentModules = tsx.filter((f) =>
+  const componentModules = markup.filter((f) =>
     !CONFIG_NAME_RE.test(f.rel) && !ROOT_NAME_RE.test(f.rel) && countTags(f.text) > 0);
   const nonEntry = componentModules.filter((f) => !isEntryFile(f.rel));
+  const allText = files.map((f) => f.text).join("\n");
+  const markupText = markup.map((f) => f.text).join("\n");
 
   const totalTags = componentModules.reduce((s, f) => s + countTags(f.text), 0) || 1;
-  const entryFiles = componentModules.filter((f) => isEntryFile(f.rel));
   const maxFileTags = Math.max(0, ...componentModules.map((f) => countTags(f.text)));
-  const dominance = maxFileTags / totalTags; // 1.0 = one giant file
+  const kTags = totalTags / 1000;
 
-  // Section-named components (semantic top-level blocks). Tokenize the file path +
-  // component names into words (splitting camelCase, kebab, snake, slashes) so both
-  // `hero-section.tsx` and `HeroSection` are credited.
-  const isSectionFile = (f: SrcFile): boolean => {
-    const raw = f.rel + " " + componentNames(f.text).join(" ");
-    const words = new Set(raw.replace(/([a-z0-9])([A-Z])/g, "$1 $2").toLowerCase().split(/[^a-z0-9]+/).filter(Boolean));
-    return SECTION_WORDS.some((w) => words.has(w));
+  const offenders: Offender[] = [];
+  const caps: string[] = [];
+
+  // =========================================================================
+  // 1. PAYLOAD DISCIPLINE — no file/line/blob a human cannot open.
+  // =========================================================================
+  let worstFileBytes = 0, worstFileRel = "";
+  let worstLine = 0, worstLineRel = "";
+  let totalInlineBytes = 0, worstInlineRel = "", worstInlineBytes = 0;
+  for (const f of files) {
+    const p = filePayload(f);
+    if (p.bytes > worstFileBytes) { worstFileBytes = p.bytes; worstFileRel = f.rel; }
+    if (p.maxLine > worstLine) { worstLine = p.maxLine; worstLineRel = f.rel; }
+    totalInlineBytes += p.inlineBytes;
+    if (p.inlineBytes > worstInlineBytes) { worstInlineBytes = p.inlineBytes; worstInlineRel = f.rel; }
+  }
+  if (worstFileRel) offenders.push({ file: worstFileRel, metric: "file bytes", value: worstFileBytes });
+  if (worstLineRel) offenders.push({ file: worstLineRel, metric: "max line chars", value: worstLine });
+  if (worstInlineBytes > 0) offenders.push({ file: worstInlineRel, metric: "inline blob bytes", value: worstInlineBytes });
+
+  // Worst-file penalty, tempered by how WIDESPREAD oversized files are: one big section
+  // in an otherwise-small tree is forgivable; many oversized files is systemic bloat.
+  const oversized = files.filter((f) => f.text.length >= K.FILE_BYTES_GOOD * 2).length;
+  const pFileMax = penalize(worstFileBytes, K.FILE_BYTES_GOOD, K.FILE_BYTES_BAD);
+  const pFileSpread = penalize(oversized, 0, Math.max(3, files.length * 0.25));
+  const pFile = 0.6 * pFileMax + 0.4 * pFileSpread;
+  const pLine = penalize(worstLine, K.LINE_CHARS_GOOD, K.LINE_CHARS_BAD);
+  const pInline = penalize(totalInlineBytes, K.INLINE_BYTES_GOOD, K.INLINE_BYTES_BAD);
+  const payloadSub = 0.4 * pFile + 0.35 * pLine + 0.25 * pInline;
+
+  // =========================================================================
+  // 2. COMPONENT DECOMPOSITION — is the page a monolith?
+  // =========================================================================
+  const dominance = maxFileTags / totalTags; // 1.0 = one giant file holds the page
+  const bigSections = componentModules.filter((f) => f.lines >= K.BIG_SECTION_LINES && !isEntryFile(f.rel)).length;
+  for (const f of componentModules) {
+    if (f.lines >= K.BIG_SECTION_LINES && !isEntryFile(f.rel)) offenders.push({ file: f.rel, metric: "section LOC", value: f.lines });
+  }
+  const dMono = penalize(dominance, K.MONOLITH_DOMINANCE_GOOD, K.MONOLITH_DOMINANCE_BAD);
+  const dCount = ramp(nonEntry.length, 0, K.COMPONENTS_GOOD);
+  const dBig = penalize(bigSections, 0, 3);
+  const decompositionSub = 0.45 * dMono + 0.3 * dCount + 0.25 * dBig;
+
+  // =========================================================================
+  // 3. DUPLICATION — repeated helpers, near-identical components, repeated SVG paths.
+  // =========================================================================
+  let helperDefs = 0, helperDups = 0;
+  for (const f of runtimeFiles) { const d = duplicateHelpers(f.text); helperDefs += d.defs; helperDups += d.dups; }
+  const svgDup = svgPathDuplication(markupText);
+  // Near-dup signatures over NON-trivial CONTENT components only: vectorized assets
+  // (icons, logos, illustration frames) legitimately share a tag shape, so counting
+  // them as "duplicates" would punish healthy asset sets rather than real copy-paste.
+  const isAssetFile = (rel: string): boolean => /(^|\/)svgs?\//i.test(rel) || /(icon|illustration|logo)\d*\.[jt]sx$/i.test(basename(rel));
+  const compSigs = nonEntry.filter((f) => !isAssetFile(f.rel)).map((f) => {
+    const h = tagHistogram(f.text);
+    const tags = Object.values(h).reduce((a, b) => a + b, 0);
+    if (tags < K.NEAR_DUP_MIN_TAGS) return "";
+    return Object.keys(h).sort().map((k) => `${k}:${h[k]}`).join(",");
+  }).filter((s) => s.length > 0);
+  const nearDup = nearDuplicateComponents(compSigs);
+
+  const helperDupRatio = helperDefs ? helperDups / helperDefs : 0;
+  const svgDupRatio = svgDup.total ? svgDup.repeats / svgDup.total : 0;
+  if (helperDups > 0) offenders.push({ file: "(helpers)", metric: "duplicate helper defs", value: helperDups });
+  if (svgDup.repeats > 0) offenders.push({ file: "(inline svg)", metric: "repeated <path> strings", value: svgDup.repeats });
+  if (nearDup > 0) offenders.push({ file: "(components)", metric: "near-identical component pairs", value: nearDup });
+
+  const uHelper = penalize(helperDupRatio, 0, K.DUP_HELPER_RATIO_BAD);
+  const uSvg = penalize(svgDupRatio, 0, K.DUP_SVG_PATH_RATIO_BAD);
+  const uNear = penalize(nearDup, 0, K.NEAR_DUP_COMPONENT_BAD);
+  // Helper duplication is the strongest tell; near-dup components second; inline-SVG
+  // path repeats are the weakest (shared icon sets repeat legitimately).
+  const duplicationSub = 0.5 * uHelper + 0.35 * uNear + 0.15 * uSvg;
+
+  // =========================================================================
+  // 4. SEMANTICS / A11Y — real tags over div soup, one h1, alt coverage, no aria traps.
+  // =========================================================================
+  const hist = tagHistogram(markupText);
+  const totalEls = Object.values(hist).reduce((a, b) => a + b, 0) || 1;
+  const divLike = (hist["div"] ?? 0) + (hist["span"] ?? 0);
+  const semanticTags = (hist["section"] ?? 0) + (hist["nav"] ?? 0) + (hist["header"] ?? 0) + (hist["footer"] ?? 0)
+    + (hist["main"] ?? 0) + (hist["article"] ?? 0) + (hist["aside"] ?? 0) + (hist["button"] ?? 0)
+    + (hist["h1"] ?? 0) + (hist["h2"] ?? 0) + (hist["h3"] ?? 0) + (hist["ul"] ?? 0) + (hist["nav"] ?? 0);
+  const h1Count = hist["h1"] ?? 0;
+  const imgCount = hist["img"] ?? 0;
+  const altCount = (markupText.match(/\balt\s*=/g) ?? []).length;
+  const ariaHidden = ariaHiddenFocusables(markupText);
+  const divRatio = divLike / totalEls;
+  const altCoverage = imgCount ? clamp01(altCount / imgCount) : 1;
+
+  if (h1Count === 0) offenders.push({ file: "(page)", metric: "h1 count", value: 0 });
+  if (ariaHidden > 0) offenders.push({ file: "(markup)", metric: "aria-hidden on focusables", value: ariaHidden });
+  if (imgCount && altCoverage < K.ALT_COVERAGE_GOOD) offenders.push({ file: "(markup)", metric: "imgs missing alt", value: imgCount - altCount });
+
+  const aDiv = penalize(divRatio, K.DIV_RATIO_GOOD, K.DIV_RATIO_BAD);
+  const aSem = clamp01(semanticTags / (totalEls * 0.12)); // ~12% semantic tags → full credit
+  const aH1 = h1Count === K.H1_REQUIRED ? 1 : h1Count > K.H1_REQUIRED ? 0.8 : 0.1; // missing h1 is a heavy penalty; multiple h1 a minor ding
+  const aAlt = altCoverage;
+  const aAria = penalize(ariaHidden, 0, 6);
+  const semanticsSub = 0.3 * aDiv + 0.2 * aSem + 0.25 * aH1 + 0.15 * aAlt + 0.1 * aAria;
+
+  // =========================================================================
+  // 5. HYGIENE — whitespace literals, frozen sub-pixels, opaque tokens, probe leaks.
+  // =========================================================================
+  const wsLiterals = whitespaceLiterals(markupText);
+  const subpixel = subpixelArbitraries(allText);
+  let propTotal = 0, propOpaque = 0;
+  for (const f of css) { const t = customPropTokens(f.text); propTotal += t.total; propOpaque += t.opaque; }
+  const probes = probeArtifacts(allText);
+  const opaqueRatio = propTotal ? propOpaque / propTotal : 0;
+  const wsPerK = wsLiterals / Math.max(1, kTags);
+  const subpixelPerK = subpixel / Math.max(1, kTags);
+
+  if (wsLiterals > 0) offenders.push({ file: "(markup)", metric: "{\" \"} whitespace literals", value: wsLiterals });
+  if (subpixel > 0) offenders.push({ file: "(styles)", metric: "frozen sub-pixel arbitraries", value: subpixel });
+  if (propOpaque > 0) offenders.push({ file: "(css)", metric: "opaque --token defs", value: propOpaque });
+  if (probes > 0) offenders.push({ file: "(markup)", metric: "capture-probe artifacts", value: probes });
+
+  const hWs = penalize(wsPerK, K.WS_LITERAL_PER_KTAG_GOOD, K.WS_LITERAL_PER_KTAG_BAD);
+  const hSub = penalize(subpixelPerK, K.SUBPIXEL_PER_KTAG_GOOD, K.SUBPIXEL_PER_KTAG_BAD);
+  const hTok = penalize(opaqueRatio, 0, K.OPAQUE_TOKEN_RATIO_BAD);
+  const hProbe = penalize(probes, 0, K.PROBE_ARTIFACTS_BAD);
+  const hygieneSub = 0.28 * hWs + 0.28 * hSub + 0.28 * hTok + 0.16 * hProbe;
+
+  // =========================================================================
+  // 6. RUNTIME DISCIPLINE — no leaked listeners, no undeclared imports.
+  // =========================================================================
+  let leaks = 0;
+  for (const f of runtimeFiles) leaks += uncleanedListeners(f.text);
+  const undeclaredImports = countUndeclaredImports(runtimeFiles);
+  if (leaks > 0) offenders.push({ file: "(runtime)", metric: "uncleaned addEventListener", value: leaks });
+  if (undeclaredImports > 0) offenders.push({ file: "(runtime)", metric: "undeclared imports", value: undeclaredImports });
+
+  const rLeak = penalize(leaks, K.LEAK_LISTENERS_GOOD, K.LEAK_LISTENERS_BAD);
+  const rImp = penalize(undeclaredImports, 0, 6);
+  const runtimeSub = 0.7 * rLeak + 0.3 * rImp;
+
+  // =========================================================================
+  // BLEND + HARD CAPS
+  // =========================================================================
+  const dims = {
+    payload: payloadSub,
+    decomposition: decompositionSub,
+    duplication: duplicationSub,
+    semantics: semanticsSub,
+    hygiene: hygieneSub,
+    runtime: runtimeSub,
   };
-  const sectionComponents = nonEntry.filter(isSectionFile).length;
-  const svgFiles = componentModules.filter((f) => /(^|\/)svgs?\//i.test(f.rel) || /icon/i.test(basename(f.rel)) || (countTags(f.text) > 0 && /^[^<]*<svg/m.test(f.text.replace(/import[^\n]*\n/g, "")))).length;
+  let total = 0;
+  for (const [k, sub] of Object.entries(dims)) total += WEIGHTS[k as keyof typeof WEIGHTS] * sub;
 
-  // ---- naming ----
-  const allComponentNames = new Set<string>();
-  for (const f of componentModules) for (const n of componentNames(f.text)) allComponentNames.add(n);
-  // exclude the page/Page entry symbol from the semantic judgement
-  const judgedNames = [...allComponentNames].filter((n) => n !== "Page" && n !== "default" && n !== "RootLayout" && n !== "Layout");
-  const genericNames = judgedNames.filter((n) => GENERIC_COMP_RE.test(n)).length;
-  const compNameSemanticRatio = judgedNames.length ? 1 - genericNames / judgedNames.length : 0;
-
-  const allClassToks: string[] = [];
-  for (const f of tsx) allClassToks.push(...classTokens(f.text));
-  const classTotal = allClassToks.length || 1;
-  const opaqueClasses = allClassToks.filter(isOpaqueClass).length;
-  const classSemanticRatio = 1 - opaqueClasses / classTotal;
-  const distinctClasses = new Set(allClassToks).size || 1;
-  const classReuse = 1 - distinctClasses / classTotal; // 0 = every class used once (per-node), →1 = heavy reuse
-
-  // content field naming + editability
-  const contentFiles = files.filter((f) => /(content|data)\.[jt]s$/i.test(basename(f.rel)) || /(^|\/)(content|lib)\//i.test(f.rel));
-  const fieldNames: string[] = [];
-  for (const f of contentFiles) fieldNames.push(...contentFieldNames(f.text));
-  const plumbingFields = fieldNames.filter((n) => PLUMBING_FIELD_RE.test(n)).length;
-  const fieldSemanticRatio = fieldNames.length ? 1 - plumbingFields / fieldNames.length : 0.5;
-
-  // ---- styling system ----
-  const cssBytes = css.reduce((s, f) => s + f.text.length, 0);
-  const cssBytesPerNode = cssBytes / totalTags;
-  let tokenRefs = 0, tokenDefs = 0;
-  for (const f of css) {
-    tokenRefs += (f.text.match(/var\(--/g) ?? []).length;
-    tokenDefs += (f.text.match(/^\s*--[\w-]+\s*:/gm) ?? []).length;
+  // Catastrophe caps: any ONE unopenable payload drags the whole grade into D-range.
+  if (worstFileBytes >= K.CATASTROPHE_FILE_BYTES) caps.push(`file ${worstFileRel} is ${(worstFileBytes / 1e6).toFixed(1)}MB (>1MB)`);
+  if (worstLine >= K.CATASTROPHE_LINE_CHARS) caps.push(`line in ${worstLineRel} is ${(worstLine / 1000).toFixed(0)}KB (>100KB)`);
+  if (totalInlineBytes >= K.CATASTROPHE_INLINE_BYTES) caps.push(`${(totalInlineBytes / 1e6).toFixed(1)}MB of embedded base64/HTML (>5MB)`);
+  if (caps.length) total = Math.min(total, K.CAP_GRADE_D);
+  else {
+    // Softer warning band.
+    if (worstFileBytes >= K.WARN_FILE_BYTES) caps.push(`file ${worstFileRel} is ${(worstFileBytes / 1000).toFixed(0)}KB (>${K.WARN_FILE_BYTES / 1000}KB)`);
+    if (worstLine >= K.WARN_LINE_CHARS) caps.push(`line in ${worstLineRel} is ${(worstLine / 1000).toFixed(0)}KB (>${K.WARN_LINE_CHARS / 1000}KB)`);
+    if (caps.length) total = Math.min(total, K.CAP_GRADE_C);
   }
-  // Tailwind-style theme tokens count as token usage too (utility classes referencing roles)
-  const tailwindTokenClasses = allClassToks.filter((t) => /(^|[-:])(bg|text|border|fill|stroke|ring|from|to|via)-/.test(t)).length;
-  // per-node-unique-rule penalty: count `.cNNN{` selectors in CSS
-  let perNodeRules = 0;
-  for (const f of css) perNodeRules += (f.text.match(/\.c[a-z]?\d+\s*[\{,]/g) ?? []).length;
-  const perNodeRuleRatio = perNodeRules / totalTags; // 1.0 = a unique rule per node
+  total = r1(Math.max(0, Math.min(100, total)));
 
-  // magic literals in component markup (raw hex/rgb/px in className/style strings)
-  let magicLiterals = 0;
-  for (const f of componentModules) {
-    magicLiterals += (f.text.match(/#[0-9a-fA-F]{3,8}\b/g) ?? []).length;
-    magicLiterals += (f.text.match(/\brgba?\([^)]*\)/g) ?? []).length;
-  }
-  const magicPerNode = magicLiterals / totalTags;
-
-  // ---- idiomatic styling (the axes the old rubric was blind to) ----
-  // A px ARBITRARY value (`w-[713.938px]`, `py-[64px]`) is a measurement, not a design choice —
-  // the single biggest "machine-generated" tell. Count them across markup + hoisted class
-  // consts, vs the standard scale / rem a human writes.
-  let arbPx = 0, arbBands = 0, stdBreakpoints = 0, dataCidCount = 0;
-  for (const f of [...componentModules, ...css]) {
-    arbPx += (f.text.match(/\[[0-9]+(?:\.[0-9]+)?px\]/g) ?? []).length;
-    arbBands += (f.text.match(/(?:min|max)-\[[0-9]+px\]:/g) ?? []).length; // arbitrary midpoint media variants
-    stdBreakpoints += (f.text.match(/(?:^|[\s"'`])(?:max-)?(?:sm|md|lg|xl|2xl):/g) ?? []).length;
-    dataCidCount += (f.text.match(/data-cid/g) ?? []).length;
-  }
-  const arbPxPerNode = arbPx / totalTags;            // low is hand-authored; high is machine replay
-  const bandShare = arbBands + stdBreakpoints > 0 ? arbBands / (arbBands + stdBreakpoints) : 0; // 1 = all arbitrary
-  const dataCidPerNode = dataCidCount / totalTags;
-  // Robotic, never-hand-written comment phrases.
-  let roboticComments = 0;
-  for (const f of [...componentModules, ...css, ...files.filter((x) => x.ext === ".ts")]) {
-    roboticComments += (f.text.match(/Generated by clone-static|render-identical to the source|Do not edit by hand/g) ?? []).length;
-  }
-
-  // ---- editability ----
-  const hasContentModule = contentFiles.some((f) => /export\s+(const|type)/.test(f.text)) ? 1 : 0;
-  // Destructured props with a default value, in any function/arrow param block — counts
-  // string, array, and identifier defaults alike (a default is a default).
-  let propsWithDefaults = 0;
-  for (const f of componentModules) {
-    for (const blk of f.text.match(/\(\s*\{[^{}]*\}/g) ?? []) {
-      propsWithDefaults += (blk.match(/\b\w+\s*=\s*(?![=>])/g) ?? []).length;
-    }
-  }
-  const defaultsSignal = clamp01(propsWithDefaults / Math.max(6, nonEntry.length));
-
-  // ---- file org ----
-  const dirSet = new Set(componentModules.map((f) => f.rel.split("/").slice(0, -1).join("/")));
-  const hasSectionsDir = [...dirSet].some((d) => /sections?$/i.test(d)) ? 1 : 0;
-  const hasComponentsDir = [...dirSet].some((d) => /(components|ui)$/i.test(d)) ? 1 : 0;
-  const hasLayoutDir = [...dirSet].some((d) => /(layout|svgs?)$/i.test(d)) ? 1 : 0;
-  const orgDirs = hasSectionsDir + hasComponentsDir + hasLayoutDir;
-
-  // ---- metadata ----
-  let docHeaders = 0, annotations = 0;
-  for (const f of componentModules) {
-    docHeaders += (f.text.match(/\/\*\*[\s\S]*?\*\//g) ?? []).length;
-    // component-type annotations in attribute, object, or doc-tag form.
-    annotations += (f.text.match(/@component|data-component/g) ?? []).length;
-  }
-
-  // =========================================================================
-  // Category scoring
-  // =========================================================================
-
-  // 1. Componentization (25): many components, low single-file dominance, sections present
-  const cCount = ramp(nonEntry.length, 0, 12);        // 0 → 12+ components
-  const cDom = 1 - ramp(dominance, 0.3, 0.95);        // penalize one giant file
-  const cSections = ramp(sectionComponents, 0, 6);    // semantic sections
-  const componentization = 25 * (0.4 * cCount + 0.35 * cDom + 0.25 * cSections);
-
-  // 2. Semantic naming (25): component names, class names, content fields
-  const naming = 25 * (0.4 * compNameSemanticRatio + 0.4 * classSemanticRatio + 0.2 * fieldSemanticRatio);
-
-  // 3. Styling system (20): class reuse, tokens, low per-node verbosity, few magic literals AND
-  //    — the axes the old rubric missed — idiomatic values (standard scale/rem, not a wall of
-  //    px arbitraries) and standard breakpoints (not arbitrary midpoint bands).
-  const sReuse = clamp01(classReuse / 0.6);            // 0.6+ reuse → full marks
-  const sTokens = ramp(tokenRefs + tailwindTokenClasses, 0, Math.max(40, totalTags * 0.5));
-  const sVerbosity = 1 - clamp01(perNodeRuleRatio);    // per-node rules are bad
-  const sMagic = 1 - clamp01(magicPerNode / 0.25);
-  const sArb = 1 - clamp01(arbPxPerNode / 2);          // ~0 arb-px/node → 1; 2+/node → 0
-  const sBp = 1 - bandShare;                           // 0 arbitrary bands → 1
-  const styling = 20 * (0.22 * sReuse + 0.13 * sTokens + 0.13 * sVerbosity + 0.07 * sMagic + 0.27 * sArb + 0.18 * sBp);
-
-  // 4. Editability (15): content module, typed fields, semantic fields, prop defaults
-  const editability = 15 * (0.4 * hasContentModule + 0.3 * fieldSemanticRatio + 0.3 * defaultsSignal);
-
-  // 5. File org (10): folder structure + svgs extracted
-  const fileOrg = 10 * (0.7 * (orgDirs / 3) + 0.3 * clamp01(svgFiles / 4));
-
-  // 6. Metadata (5): concise human doc headers + semantic component annotations — but a
-  //    "Generated by clone-static / render-identical" robotic header is a NEGATIVE signal (no
-  //    human writes it), and shipping a per-node data-cid on every element is markup noise.
-  const cleanComments = roboticComments === 0 ? 1 : clamp01(1 - roboticComments / Math.max(4, nonEntry.length));
-  const lowCidNoise = 1 - clamp01(dataCidPerNode);     // ~0 data-cid/node → 1; 1/node → 0
-  const metadata = 5 * (0.35 * clamp01(docHeaders / Math.max(4, nonEntry.length)) * cleanComments
-    + 0.35 * clamp01(annotations / Math.max(8, totalTags * 0.1))
-    + 0.3 * lowCidNoise);
-
-  const total = componentization + naming + styling + editability + fileOrg + metadata;
+  // Order offenders by severity so the report's "top offenders" is meaningful.
+  offenders.sort((a, b) => severity(b) - severity(a));
 
   return {
     dir: root,
-    total: r1(total),
+    total,
+    grade: toLetter(total),
+    caps,
     categories: {
-      componentization: { score: r1(componentization), max: 25, metrics: { components: nonEntry.length, dominancePct: r1(dominance * 100), sectionComponents } },
-      naming: { score: r1(naming), max: 25, metrics: { compNameSemanticPct: r1(compNameSemanticRatio * 100), classSemanticPct: r1(classSemanticRatio * 100), fieldSemanticPct: r1(fieldSemanticRatio * 100), genericNames } },
-      styling: { score: r1(styling), max: 20, metrics: { classReusePct: r1(classReuse * 100), tokenRefs, perNodeRules, magicLiterals, arbPx, arbPxPerNode: r1(arbPxPerNode), arbBands, stdBreakpoints, bandSharePct: r1(bandShare * 100) } },
-      editability: { score: r1(editability), max: 15, metrics: { hasContentModule, fieldSemanticPct: r1(fieldSemanticRatio * 100), propsWithDefaults } },
-      fileOrg: { score: r1(fileOrg), max: 10, metrics: { orgDirs, svgFiles, hasSectionsDir, hasComponentsDir } },
-      metadata: { score: r1(metadata), max: 5, metrics: { docHeaders, annotations, roboticComments, dataCidPerNode: r1(dataCidPerNode) } },
+      payload: { score: r1(WEIGHTS.payload * payloadSub), max: WEIGHTS.payload, metrics: { maxFileKB: r1(worstFileBytes / 1000), maxLineKB: r1(worstLine / 1000), inlineBlobKB: r1(totalInlineBytes / 1000) } },
+      decomposition: { score: r1(WEIGHTS.decomposition * decompositionSub), max: WEIGHTS.decomposition, metrics: { components: nonEntry.length, dominancePct: r1(dominance * 100), bigSections } },
+      duplication: { score: r1(WEIGHTS.duplication * duplicationSub), max: WEIGHTS.duplication, metrics: { helperDups, helperDupPct: r1(helperDupRatio * 100), svgPathRepeats: svgDup.repeats, nearDupPairs: nearDup } },
+      semantics: { score: r1(WEIGHTS.semantics * semanticsSub), max: WEIGHTS.semantics, metrics: { h1: h1Count, divRatioPct: r1(divRatio * 100), semanticTags, altCoveragePct: r1(altCoverage * 100), ariaHiddenFocusables: ariaHidden } },
+      hygiene: { score: r1(WEIGHTS.hygiene * hygieneSub), max: WEIGHTS.hygiene, metrics: { wsLiterals, subpixelArbitraries: subpixel, opaqueTokenPct: r1(opaqueRatio * 100), probeArtifacts: probes } },
+      runtime: { score: r1(WEIGHTS.runtime * runtimeSub), max: WEIGHTS.runtime, metrics: { uncleanedListeners: leaks, undeclaredImports } },
     },
+    offenders: offenders.slice(0, 15),
     raw: {
       files: files.length, componentModules: componentModules.length, totalTags, maxFileTags,
-      classTokens: classTotal, distinctClasses, opaqueClasses, cssBytes,
+      worstFileBytes, worstLineChars: worstLine, inlineBytes: totalInlineBytes,
     },
   };
 }
 
+/** Undeclared imports: a bare-specifier import not present in any package.json/tsconfig
+ *  alias and not a relative path — a runtime crash waiting to happen. We approximate by
+ *  flagging imports of local-looking modules that resolve nowhere is expensive, so instead
+ *  we flag the cheap, robust tell: an import statement whose source is an empty string or a
+ *  malformed specifier. (Kept conservative to avoid false positives across frameworks.) */
+function countUndeclaredImports(files: SrcFile[]): number {
+  let n = 0;
+  for (const f of files) {
+    for (const m of f.text.matchAll(/\bimport\s+[^;]*?\bfrom\s*["'`]([^"'`]*)["'`]/g)) {
+      const spec = m[1]!;
+      if (spec.trim() === "" || /\s/.test(spec) || spec === "undefined" || spec === "null") n++;
+    }
+  }
+  return n;
+}
+
+/** Relative weight of an offender for ordering the top-offenders list. */
+function severity(o: Offender): number {
+  switch (o.metric) {
+    case "file bytes": return o.value / 1000;
+    case "max line chars": return o.value / 1000;
+    case "inline blob bytes": return o.value / 2000;
+    case "section LOC": return o.value / 20;
+    case "opaque --token defs": return o.value * 0.5;
+    case "frozen sub-pixel arbitraries": return o.value * 0.3;
+    case "{\" \"} whitespace literals": return o.value * 0.1;
+    case "h1 count": return 300; // a missing h1 is always a headline offender
+    case "uncleaned addEventListener": return o.value * 3;
+    default: return o.value;
+  }
+}
+
+// ---------------------------------------------------------------------------
+// CLI
+// ---------------------------------------------------------------------------
+
 function fmt(rep: QualityReport): string {
   const lines: string[] = [];
   lines.push(`\n  ${rep.dir}`);
-  lines.push(`  TOTAL: ${rep.total}/100`);
+  lines.push(`  GRADE: ${rep.grade}   (${rep.total}/100)`);
+  if (rep.caps.length) lines.push(`  CAPS:  ${rep.caps.join("; ")}`);
   for (const [k, c] of Object.entries(rep.categories)) {
     const metrics = Object.entries(c.metrics).map(([mk, mv]) => `${mk}=${mv}`).join(" ");
-    lines.push(`    ${k.padEnd(16)} ${String(c.score).padStart(5)}/${c.max}   ${metrics}`);
+    lines.push(`    ${k.padEnd(15)} ${String(c.score).padStart(5)}/${c.max}   ${metrics}`);
+  }
+  if (rep.offenders.length) {
+    lines.push(`    top offenders:`);
+    for (const o of rep.offenders.slice(0, 8)) lines.push(`      ${o.metric.padEnd(34)} ${String(o.value).padStart(10)}  ${o.file}`);
   }
   return lines.join("\n");
 }
@@ -353,11 +614,11 @@ async function main(): Promise<void> {
   for (const rep of reports) console.log(fmt(rep));
   if (reports.length > 1) {
     console.log("\n  ── comparison ──");
-    console.log("  " + "category".padEnd(16) + reports.map((_, i) => `app${i + 1}`.padStart(10)).join(""));
+    console.log("  " + "dimension".padEnd(15) + reports.map((_, i) => `app${i + 1}`.padStart(10)).join(""));
     for (const cat of Object.keys(reports[0]!.categories)) {
-      console.log("  " + cat.padEnd(16) + reports.map((r) => String(r.categories[cat]!.score).padStart(10)).join(""));
+      console.log("  " + cat.padEnd(15) + reports.map((r) => String(r.categories[cat]!.score).padStart(10)).join(""));
     }
-    console.log("  " + "TOTAL".padEnd(16) + reports.map((r) => String(r.total).padStart(10)).join(""));
+    console.log("  " + "GRADE".padEnd(15) + reports.map((r) => `${r.grade}(${r.total})`.padStart(10)).join(""));
   }
 }
 
diff --git a/compiler/src/site/generateSite.ts b/compiler/src/site/generateSite.ts
index d820d1c..d73265e 100644
--- a/compiler/src/site/generateSite.ts
+++ b/compiler/src/site/generateSite.ts
@@ -15,7 +15,7 @@ import { generateCss, RESET_CSS } from "../generate/css.js";
 import { generateInteractionCss } from "../generate/interactionCss.js";
 import { buildRuntimeSpecs, wiresJsx, dittoWireImportPath, DITTO_WIRE_TSX, interactionRejectedSet } from "../generate/interactive.js";
 import { buildLottieSpec, lottieHasContent, lottieWireJsx, dittoLottieImportPath, DITTO_LOTTIE_TSX } from "../generate/lottie.js";
-import { renderChildrenJsx, renderAttrs, buildComponentRegistry, componentPreamble, componentFiles, componentImports, componentDataDecls, summarizeComponents, fileBase, generateViteConfig, generateViteIndexHtml, viteGlobalsCss, PACKAGE_JSON, PACKAGE_JSON_TW, PACKAGE_JSON_VITE, PACKAGE_JSON_VITE_TW, TSCONFIG_JSON, TSCONFIG_JSON_VITE, NEXT_CONFIG, injectLottieDep, type AppFramework, type LinkRewrite, type ExtractedComponent, type RenderCtx } from "../generate/app.js";
+import { renderChildrenJsx, renderAttrs, buildComponentRegistry, componentPreamble, componentFiles, componentImports, componentDataDecls, summarizeComponents, fileBase, generateViteConfig, generateViteIndexHtml, viteGlobalsCss, cnImportLine, resolveHtmlBg, htmlBgRule, CN_UTILS_MODULE, PACKAGE_JSON, PACKAGE_JSON_TW, PACKAGE_JSON_VITE, PACKAGE_JSON_VITE_TW, TSCONFIG_JSON, TSCONFIG_JSON_VITE, NEXT_CONFIG, injectLottieDep, type AppFramework, type LinkRewrite, type ExtractedComponent, type RenderCtx } from "../generate/app.js";
 import { buildTailwind, tailwindGlobalsCss, createColorInterner, colorDefsCssOf, type TailwindOutput } from "../generate/tailwind.js";
 import type { InteractionCapture } from "../capture/interactions.js";
 import type { IRChild } from "../normalize/ir.js";
@@ -29,7 +29,7 @@ import type { CaptureResult } from "../capture/capture.js";
 import { backfillLazyBackgrounds } from "../normalize/ir.js";
 import { toRoutePath, segmentsOf } from "../crawl/url.js";
 import { buildCanonicalChrome, chromeCssIr, middleChildren, middleIncludeFilter, CHROME_PREFIX, type ChromePlan } from "./sharedLayout.js";
-import { buildSeoInventory, emitSeoAssetFiles, emitSeoRoutes, jsonLdHeadMarkup, metadataExport, routeSummaryFromIr, seoStaticFiles, viewportExport, type SeoInventory, type SeoRouteSummary } from "../generate/seo.js";
+import { buildSeoInventory, emitSeoAssetFiles, emitSeoRoutes, jsonLdHeadMarkup, metadataExport, routeSummaryFromIr, seoStaticFiles, SITE_ORIGIN_LAYOUT_IMPORT, SITE_ORIGIN_MODULE, viewportExport, type SeoInventory, type SeoRouteSummary } from "../generate/seo.js";
 import { emitGeneratedDocs } from "../generate/docs.js";
 
 export type RouteArtifact = {
@@ -91,10 +91,10 @@ function unionFontCss(routes: RouteArtifact[]): string {
 
 /** Shared page-base bits (entry html background + overflow-x clip) — same rationale as
  *  single-page generation; used by both the plain-CSS and Tailwind globals. */
-function pageBaseOf(entry: RouteArtifact): { htmlBg: string; clip: string } {
+function pageBaseOf(entry: RouteArtifact): { htmlBg: string | null; clip: string } {
   const cw = entry.ir.doc.canonicalViewport;
   const pv = entry.ir.doc.perViewport[cw];
-  const htmlBg = pv?.htmlBg && pv.htmlBg !== "rgba(0, 0, 0, 0)" ? pv.htmlBg : (pv?.bodyBg ?? "#ffffff");
+  const htmlBg = resolveHtmlBg(pv);
   const noHScroll = Object.entries(entry.ir.doc.perViewport).every(([vp, d]) => d.scrollWidth <= Number(vp) * 1.03);
   return { htmlBg, clip: noHScroll ? "\nhtml, body { overflow-x: clip; }" : "" };
 }
@@ -112,8 +112,7 @@ ${paletteCss}
 ${tokensToCss(entry.tokens, true)}
 
 /* page base */
-html { background: ${htmlBg}; }
-body { font-family: ${SYSTEM_FALLBACK}; }${clip}
+${htmlBgRule(htmlBg)}body { font-family: ${SYSTEM_FALLBACK}; }${clip}
 `;
 }
 
@@ -132,9 +131,10 @@ function layoutTsx(entry: RouteArtifact, bodyClass: string | undefined, chrome?:
   const viewport = seo ? viewportExport(seo) : `export const viewport = { width: "device-width", initialScale: 1 };\n`;
   const jsonLd = seo ? jsonLdHeadMarkup(seo, 8) : "";
   const head = jsonLd ? `      <head>\n${jsonLd}\n      </head>\n` : "";
+  const siteImport = seo ? SITE_ORIGIN_LAYOUT_IMPORT + "\n" : "";
   return `import "./globals.css";
 ${chromeImport}import type { ReactNode } from "react";
-
+${siteImport}
 ${metadata}${viewport}
 
 ${pre}export default function RootLayout({ children }: { children: ReactNode }) {
@@ -271,6 +271,9 @@ export function generateSiteApp(opts: {
   // package.json is written after the route loop (below) so the lottie-web dependency can be
   // added when any route actually replays a Lottie animation.
   writeText(join(appDir, "tsconfig.json"), isVite ? TSCONFIG_JSON_VITE : TSCONFIG_JSON);
+  writeText(join(appDir, "src", "lib", "utils.ts"), CN_UTILS_MODULE);
+  // SITE_ORIGIN constant for SEO/metadata routes (Next only — Vite ships static SEO files).
+  if (!isVite) writeText(join(appDir, "src", "lib", "site.ts"), SITE_ORIGIN_MODULE);
   writeText(join(appDir, ".gitignore"), "node_modules\n.next\nout\ndist\n");
   if (isVite) {
     rmSync(join(appDir, "next.config.mjs"), { force: true });
@@ -384,11 +387,17 @@ export function generateSiteApp(opts: {
     // Stage 6: split each route component into its own route-local `components/Name.tsx`
     // (page imports them); per-route data stays inline. Route-local dirs keep names from
     // colliding across routes, which each name their components independently.
-    for (const { name, module } of componentFiles(routeReg)) writeText(join(routeDir, "components", fileBase(name) + ".tsx"), module);
+    // Depth of a route-local `components/Name.tsx` below `src`: src/app/<dir>/components
+    // (Next) or src/routes/<key>/components (Vite). +1 for the components dir itself.
+    const compDepth = (isVite ? 2 : (dir ? dir.split("/").length + 1 : 1)) + 1;
+    for (const { name, module } of componentFiles(routeReg, undefined, compDepth)) writeText(join(routeDir, "components", fileBase(name) + ".tsx"), module);
     const compImport = componentImports(routeReg, 0); // route-local → ./components/Name
     const dataDecls = componentDataDecls(routeReg);
     const preBlock = dataDecls ? dataDecls + "\n\n" : "";
-    const importLines = [wireImport.trimEnd(), lottieImport.trimEnd(), compImport].filter(Boolean).join("\n");
+    // page.tsx sits at routeDir (src/app/<dir> or src/routes/<key>); depth below src.
+    const pageDepth = isVite ? 2 : (dir ? dir.split("/").length + 1 : 1);
+    const cnImport = /\bcn\(/.test(bodyJsx) ? cnImportLine(pageDepth) + "\n" : "";
+    const importLines = [wireImport.trimEnd(), lottieImport.trimEnd(), cnImport.trimEnd(), compImport].filter(Boolean).join("\n");
     const pageTsx = `${isVite ? "" : 'import "./ditto.css";\n'}${importLines ? importLines + "\n" : ""}// Generated by clone-site. Do not edit by hand.\n${preBlock}export default function Page() {\n  return (\n    <>\n${bodyJsx}${wireBody}${lottieBody}
     </>
   );
diff --git a/compiler/src/validate/gates.ts b/compiler/src/validate/gates.ts
index 8796af8..9f9ed4f 100644
--- a/compiler/src/validate/gates.ts
+++ b/compiler/src/validate/gates.ts
@@ -1,5 +1,5 @@
 import type { IR, IRNode } from "../normalize/ir.js";
-import { isTextChild } from "../normalize/ir.js";
+import { isTextChild, irContentExtent } from "../normalize/ir.js";
 import type { PageSnapshot } from "../capture/walker.js";
 import type { GenNode } from "./render.js";
 import { indexByCid } from "./render.js";
@@ -86,6 +86,32 @@ function hasVisibleElementChild(node: IRNode, vp: number): boolean {
   return false;
 }
 
+/** A source text node that the capture painted VISIBLE but the clone rendered HIDDEN at the same
+ *  viewport is a high-signal regression: the words are in the markup yet fall in an invisible gen
+ *  subtree (off-viewport-shifted, banded-hidden, or width-frozen off-screen). Cheap to detect —
+ *  the gen node exists (matched by cid) but reports `visible === false`. Counts DISTINCT source
+ *  cids over the run (a node hidden at several viewports counts once) so the number reads as
+ *  "how many text nodes went dark", not "hidden-node×viewport". Non-blocking: reported as a metric
+ *  only. Pure + input-driven → deterministic. */
+export function countVisibleInCaptureHiddenInClone(
+  ir: IR,
+  genSnaps: Record<number, PageSnapshot>,
+  viewports: number[],
+): number {
+  const hiddenCids = new Set<string>();
+  for (const vp of viewports) {
+    if (!genSnaps[vp]) continue;
+    const gen = indexByCid(genSnaps[vp]!);
+    for (const s of collectSrcNodes(ir, vp)) {
+      if (!s.visible) continue;
+      if (normText(s.directText).length === 0) continue;
+      const g = gen.get(s.node.id);
+      if (g && !g.visible) hiddenCids.add(s.node.id);
+    }
+  }
+  return hiddenCids.size;
+}
+
 // ---------- Pollution gate (stage 2): is the captured page degenerate? ----------
 // A clone can pass every structural gate while faithfully reproducing the WRONG
 // page: an egress/bot wall, a near-empty shell, or a cookie/consent modal that was
@@ -119,11 +145,30 @@ export function gatePollution(ir: IR, capture: CaptureResult, viewports: number[
   let blocking = capture.dismissal?.blocking ?? false;
   for (const pv of capture.perViewport) { overlaysRemaining = Math.max(overlaysRemaining, pv.overlaysRemaining ?? 0); blocking = blocking || !!pv.blocking; }
   let minHeightRatio = Infinity;
+  let maxHeightRatio = 0;
   for (const pv of capture.perViewport) {
-    if (pv.height > 0) minHeightRatio = Math.min(minHeightRatio, pv.scrollHeight / pv.height);
+    if (pv.height > 0) {
+      const ratio = pv.scrollHeight / pv.height;
+      minHeightRatio = Math.min(minHeightRatio, ratio);
+      maxHeightRatio = Math.max(maxHeightRatio, ratio);
+    }
   }
   if (!Number.isFinite(minHeightRatio)) minHeightRatio = 1;
 
+  // Scroll-locked-capture contradiction: an email-capture/promo popup that sets
+  // body{overflow:hidden;height:100vh} collapses `document.scrollHeight` to EXACTLY the viewport
+  // height at EVERY width (ratio ~1.0 across the board) — yet the real page's IN-FLOW content
+  // (the IR's sections) still lays out several viewports tall. A genuine one-screen landing page
+  // has content extent ~= its scrollHeight, so this only fires when the two disagree: captured
+  // scrollHeight pinned to one viewport WHILE the IR content spans multiple. That is a
+  // scroll-locked, polluted capture — the overlay detector should have caught it, so fail loudly.
+  let maxContentRatio = 0;
+  for (const pv of capture.perViewport) {
+    if (pv.height > 0) maxContentRatio = Math.max(maxContentRatio, irContentExtent(ir.root, pv.viewport) / pv.height);
+  }
+  // scrollHeight never exceeds ~1 viewport at any width, but the IR content is 2+ viewports tall.
+  const scrollLockedContradiction = maxHeightRatio > 0 && maxHeightRatio < 1.15 && maxContentRatio >= 2;
+
   // Degenerate signals. Calibrated against real captures: an egress/bot wall is
   // ~3 nodes / ~24 chars; the most minimal legitimate page in the suite
   // (michaelcole.me) is 26 nodes / 640 chars. Thresholds sit safely between.
@@ -131,6 +176,7 @@ export function gatePollution(ir: IR, capture: CaptureResult, viewports: number[
   if (wall && nodeCount < 220) issues.push("bot/egress wall text on a small page");
   if (textChars < 60 && nodeCount < 50) issues.push(`near-empty page: ${textChars} visible text chars, ${nodeCount} nodes`);
   if (blocking) issues.push("a full-viewport modal still scroll-locks the page after dismissal");
+  if (scrollLockedContradiction) issues.push(`scroll-locked capture: scrollHeight pinned to ~1 viewport at every width while IR content spans ${round2(maxContentRatio)} viewports`);
 
   return {
     gate: "pollution",
@@ -138,6 +184,7 @@ export function gatePollution(ir: IR, capture: CaptureResult, viewports: number[
     metrics: {
       nodeCount, visibleTextChars: textChars, wallTextDetected: wall,
       overlaysRemaining, blocking, minScrollHeightRatio: round2(minHeightRatio),
+      maxScrollHeightRatio: round2(maxHeightRatio), maxContentExtentRatio: round2(maxContentRatio),
       dismissedCount: capture.dismissal?.dismissed.length ?? 0,
       overlaysRemoved: capture.dismissal?.removed ?? 0,
       videoStills: capture.dismissal?.videoStills ?? 0,
@@ -175,7 +222,7 @@ export function gate2Assets(assetGraph: AssetGraph, fontGraph: FontGraph, gen: {
   if (zeroByte > 0) issues.push(`${zeroByte} zero-byte downloaded assets`);
   if (skippedNoReason > 0) issues.push(`${skippedNoReason} skipped assets without reason`);
   if (gen.remoteRefs.length > 0) issues.push(`${gen.remoteRefs.length} generated refs point to remote origin`);
-  if (gen.failed404.length > 0) issues.push(`${gen.failed404.length} generated asset refs 404`);
+  if (gen.failed404.length > 0) issues.push(`${gen.failed404.length} generated asset refs missing (HTTP >= 400 or file absent from export)`);
   const fontsResolvedOrFallback = fontGraph.entries.every((f) => f.status === "resolved" || (f.status === "fallback" && f.reason));
   if (!fontsResolvedOrFallback) issues.push("font declarations not resolved/fallback-recorded");
   return {
@@ -257,6 +304,12 @@ export function gate3Dom(ir: IR, genSnaps: Record<number, PageSnapshot>, viewpor
     }
   }
 
+  // Non-blocking, high-signal diagnostic: source text the capture painted VISIBLE that the clone
+  // renders HIDDEN at the same viewport (off-screen-shifted / banded / width-frozen subtree). Does
+  // NOT gate pass — text presence already covers markup fidelity — but surfaces the "went dark"
+  // count so a banner/feed row vanishing is legible in the report instead of hiding inside a 99.x.
+  const textHiddenInClone = countVisibleInCaptureHiddenInClone(ir, genSnaps, viewports);
+
   const matchPct = totalVisible ? matched / totalVisible : 1;
   const textPct = textTotal ? textPresent / textTotal : 1;
   const linkPct = linksTotal ? linksOk / linksTotal : 1;
@@ -275,6 +328,7 @@ export function gate3Dom(ir: IR, genSnaps: Record<number, PageSnapshot>, viewpor
       nodeMatchPct: round4(matchPct), textPresentPct: round4(textPct),
       linkPct: round4(linkPct), mediaPct: round4(mediaPct),
       totalVisible, matched, textTotal, textPresent, linksTotal, mediaTotal, inventedText,
+      textHiddenInClone,
     },
     issues,
   };
@@ -292,8 +346,12 @@ function isValidRetag(srcTag: string, genTag: string): boolean {
   return genTag === "div" && /^(ul|ol|menu|dl|p|h[1-6])$/.test(srcTag); // content-model → div
 }
 
-function normHref(href: string, origin: string): string {
+export function normHref(href: string, origin: string): string {
   if (!href) return "";
+  // A `javascript:*` href is a script trigger, not a navigable URL. Generation emits an inert `#`
+  // for it (React blocks the literal), so treat every javascript: href — on either side — as `#`
+  // and let the two sides match instead of failing on the un-reproducible script string.
+  if (/^\s*javascript:/i.test(href)) return "#";
   if (href.startsWith("#")) return href;
   try {
     const u = new URL(href, origin);
@@ -346,7 +404,10 @@ export function gate4Style(ir: IR, genSnaps: Record<number, PageSnapshot>, viewp
         // equal, only numerically far apart. Treat any two such large radii as equivalent so the
         // idiomatic `rounded-full` doesn't trip the exact-px compare; real radii stay ±2px.
         if (p === "borderTopLeftRadius" && pxNum(s.computed[p] ?? "") >= PILL_PX && pxNum(g.computed[p] ?? "") >= PILL_PX) continue;
-        if (!cmpNum(s.computed[p], g.computed[p], 2, 0)) { nodeOk = false; fails.push(p); }
+        const eq = p === "letterSpacing"
+          ? letterSpacingEquivalent(s.computed[p], g.computed[p])
+          : cmpNum(s.computed[p], g.computed[p], 2, 0);
+        if (!eq) { nodeOk = false; fails.push(p); }
       }
       for (const p of PX4_PROPS) {
         // `gap: normal` is the initial value and resolves to 0 for flex/grid, so it
@@ -405,6 +466,19 @@ function cmpNum(a: string | undefined, b: string | undefined, abs: number, pct:
   return withinAbs(na, nb, abs) || (pct > 0 && withinPct(na, nb, pct));
 }
 
+/** Compare two computed `letter-spacing` values within the ±2px style tolerance, treating the keyword
+ *  `normal` as `0px`. `letter-spacing: normal` is the initial value and adds no extra spacing (it
+ *  computes to 0), so `normal` ≡ `0px`; crucially, Chromium serializes a computed `letter-spacing: 0`
+ *  BACK as the keyword `normal`, so a genuinely-zero (or sub-0.1px, snapped-to-zero) tracking shows up
+ *  as `normal` on one side and `0px` on the other — a spelling difference that `cmpNum` alone reads as
+ *  a NaN → exact-string mismatch. Normalizing the keyword before the numeric compare removes that false
+ *  failure while a real tracking delta (> 2px) still fails. Mirrors the `gap: normal → 0px` handling. */
+export function letterSpacingEquivalent(a: string | undefined, b: string | undefined): boolean {
+  if (a === undefined) return true;
+  const norm = (v: string | undefined): string => (v ?? "").replace(/\bnormal\b/g, "0px");
+  return cmpNum(norm(a), norm(b), 2, 0);
+}
+
 // ---------- Gate 5: layout / section equivalence ----------
 export function gate5Layout(ir: IR, genSnaps: Record<number, PageSnapshot>, sections: Section[], viewports: number[], reflow = false): GateResult {
   const issues: string[] = [];
diff --git a/compiler/src/validate/interactionGate.ts b/compiler/src/validate/interactionGate.ts
index 50db554..a34305d 100644
--- a/compiler/src/validate/interactionGate.ts
+++ b/compiler/src/validate/interactionGate.ts
@@ -4,6 +4,7 @@ import type { InteractionCapture } from "../capture/interactions.js";
 import { buildRuntimeSpecs, specKey } from "../generate/interactive.js";
 import { buildMenuSpecs } from "../generate/menu.js";
 import type { GateResult } from "./gates.js";
+import { gotoAndSettle } from "./render.js";
 
 /**
  * Stage 4 interaction gate. Drives the SAME interactions in the built clone that
@@ -61,7 +62,10 @@ export async function driveInteractionGate(opts: {
     const ctx = await browser.newContext({ viewport: { width: vp, height: vh }, deviceScaleFactor: 1 });
     const page = await ctx.newPage();
     await page.addInitScript("globalThis.__name = globalThis.__name || ((fn) => fn);");
-    await page.goto(url, { waitUntil: "networkidle", timeout: 45000 });
+    // `load` + bounded network-quiet wait (not strict `networkidle`) so an autoplaying
+    // long hero video — which keeps issuing bounded range fetches — can't make navigation
+    // time out and fail the interaction gate before any interaction is even driven.
+    await gotoAndSettle(page, url);
     await page.waitForTimeout(300);
 
     const styleOf = (cid: string, props: string[]): Promise<Record<string, string> | null> =>
diff --git a/compiler/src/validate/render.ts b/compiler/src/validate/render.ts
index 8acbb73..8c0d8fd 100644
--- a/compiler/src/validate/render.ts
+++ b/compiler/src/validate/render.ts
@@ -5,6 +5,7 @@ import { join, extname, normalize } from "node:path";
 import { spawnSync } from "node:child_process";
 import { chromium } from "playwright";
 import { collectPage, type PageSnapshot } from "../capture/walker.js";
+import { captureFullPageViaCDP, normalizeVideoTime } from "../capture/capture.js";
 import { ensureDir, writeJSONCompact } from "../util/fsx.js";
 
 const ESBUILD_SHIM =
@@ -145,6 +146,50 @@ async function readLimited(p: string): Promise<Buffer> {
   }
 }
 
+/** Result of interpreting a `Range` header against a known resource size.
+ *  - `kind: "full"`  → no (usable) Range header; answer with a normal 200 full body.
+ *  - `kind: "range"` → a single satisfiable `bytes=start-end`; answer 206 with [start,end].
+ *  - `kind: "unsatisfiable"` → a syntactically valid range wholly past EOF; answer 416. */
+export type RangeResolution =
+  | { kind: "full" }
+  | { kind: "range"; start: number; end: number }
+  | { kind: "unsatisfiable" };
+
+/** Parse a single-range HTTP `Range` header ("bytes=start-end", "bytes=start-",
+ *  "bytes=-suffix") against a resource of `size` bytes. Multi-range ("a-b,c-d") is
+ *  intentionally collapsed to a full 200 (Chromium's media element only ever asks for a
+ *  single range, and RFC 7233 lets a server ignore Range and reply 200). Anything the
+ *  spec calls malformed (missing "bytes=", non-numeric, inverted, both bounds empty) is
+ *  also treated as "full" — the safe fallback. A well-formed range that starts at or past
+ *  EOF is "unsatisfiable" → 416. `end` is inclusive and clamped to size-1. */
+export function parseRangeHeader(header: string | undefined, size: number): RangeResolution {
+  if (!header) return { kind: "full" };
+  const m = /^bytes=(\d*)-(\d*)$/.exec(header.trim());
+  if (!m) return { kind: "full" }; // absent/malformed/multi-range → serve full body
+  const startStr = m[1]!;
+  const endStr = m[2]!;
+  if (startStr === "" && endStr === "") return { kind: "full" }; // "bytes=-" is malformed
+  if (size <= 0) return { kind: "unsatisfiable" };
+  let start: number;
+  let end: number;
+  if (startStr === "") {
+    // Suffix range: "bytes=-N" → last N bytes.
+    const suffix = Number(endStr);
+    if (!Number.isFinite(suffix) || suffix <= 0) return { kind: "full" };
+    start = Math.max(0, size - suffix);
+    end = size - 1;
+  } else {
+    start = Number(startStr);
+    if (!Number.isFinite(start)) return { kind: "full" };
+    if (start >= size) return { kind: "unsatisfiable" }; // start past EOF
+    end = endStr === "" ? size - 1 : Number(endStr);
+    if (!Number.isFinite(end)) return { kind: "full" };
+    if (end < start) return { kind: "full" }; // inverted → ignore Range
+    end = Math.min(end, size - 1);
+  }
+  return { kind: "range", start, end };
+}
+
 export function serveStatic(rootDir: string): Promise<{ url: string; close: () => Promise<void> }> {
   const server: Server = createServer(async (req, res) => {
     try {
@@ -167,8 +212,32 @@ export function serveStatic(rootDir: string): Promise<{ url: string; close: () =
         if (existsSync(fallback)) { res.writeHead(404, { "content-type": "text/html" }); res.end(await readLimited(fallback)); return; }
         res.writeHead(404); res.end("not found"); return;
       }
+      const contentType = CONTENT_TYPES[extname(filePath).toLowerCase()] ?? "application/octet-stream";
+      const size = statSync(filePath).size;
+      // HTTP Range support (RFC 7233). Chromium requests <video>/<audio> with `Range: bytes=0-`
+      // and, absent a 206, holds the single progressive stream open throttled to playback — a
+      // long autoplay hero (76s) then means `waitUntil:"networkidle"` can mathematically never
+      // fire. Answering 206 with bounded chunks lets Chromium fetch in pieces so the network
+      // goes idle between reads. A HEAD-style range far past EOF gets a 416.
+      const range = parseRangeHeader(req.headers.range as string | undefined, size);
+      if (range.kind === "unsatisfiable") {
+        res.writeHead(416, { "content-type": contentType, "content-range": `bytes */${size}`, "accept-ranges": "bytes" });
+        res.end();
+        return;
+      }
       const data = await readLimited(filePath);
-      res.writeHead(200, { "content-type": CONTENT_TYPES[extname(filePath).toLowerCase()] ?? "application/octet-stream" });
+      if (range.kind === "range") {
+        const chunk = data.subarray(range.start, range.end + 1);
+        res.writeHead(206, {
+          "content-type": contentType,
+          "content-range": `bytes ${range.start}-${range.end}/${size}`,
+          "accept-ranges": "bytes",
+          "content-length": String(chunk.length),
+        });
+        res.end(chunk);
+        return;
+      }
+      res.writeHead(200, { "content-type": contentType, "accept-ranges": "bytes", "content-length": String(data.length) });
       res.end(data);
     } catch {
       res.writeHead(500); res.end("error");
@@ -191,8 +260,151 @@ export type RenderResult = {
   runtimeErrors: string[];
   httpStatus: number;
   failedResources: string[];
+  /** Non-fatal diagnostics: families the app declared via @font-face that never reached
+   *  `status:"loaded"` within the wait bound (their text was measured with a fallback face). */
+  fontWarnings: string[];
 };
 
+/** A single entry of `document.fonts` as reported in-page, reduced to the fields the
+ *  load decision needs. Serializable so the decision logic can be unit-tested outside a browser. */
+export type FontFaceStatus = { family: string; weight: string; style: string; status: string };
+
+/** Pure decision for the font-load wait: given the current `document.fonts` entries, return the
+ *  families that are DECLARED (an @font-face exists for them) and still actively `"loading"`. Only
+ *  `"loading"` is pending: browsers lazy-load faces, so after `document.fonts.ready` a face the
+ *  rendered text actually needs is already fetching (`"loading"`), while a face left `"unloaded"`
+ *  is by definition unreferenced by any rendered text and will never load on its own — waiting on
+ *  it just burns the cap. `"loaded"`/`"error"` are terminal. Empty return ⇒ no face is still
+ *  fetching and the DOM may be measured. The check is state-based (not time-based), so the caller's
+ *  poll is deterministic: it ends the instant this returns empty, regardless of wall-clock timing. */
+export function pendingFontFamilies(faces: FontFaceStatus[]): string[] {
+  const pending = new Set<string>();
+  for (const f of faces) {
+    const fam = f.family.replace(/^["']|["']$/g, "");
+    // Only a face still actively fetching keeps its family pending; "unloaded" (unreferenced),
+    // "loaded", and "error" are all non-blocking.
+    if (f.status === "loading") pending.add(fam);
+  }
+  return [...pending].sort();
+}
+
+/** Declared @font-face faces left `"unloaded"` after the wait bound: not fetched because no
+ *  rendered text resolves to them (unreferenced weight/style/unicode-subset siblings). Reported
+ *  per-face (family+weight+style) for an informational-only log — these are benign, never a
+ *  fidelity problem, since the text that IS measured renders in the face that actually loaded. */
+export function unreferencedFontFaces(faces: FontFaceStatus[]): FontFaceStatus[] {
+  return faces
+    .filter((f) => f.status === "unloaded")
+    .map((f) => ({ family: f.family.replace(/^["']|["']$/g, ""), weight: f.weight, style: f.style, status: f.status }))
+    .sort((a, b) => `${a.family} ${a.weight} ${a.style}`.localeCompare(`${b.family} ${b.weight} ${b.style}`));
+}
+
+/** In-page: await `document.fonts.ready`, then poll (bounded) until no declared @font-face is still
+ *  `"loading"`. Browsers lazy-load faces, so once ready has fired the faces the rendered text needs
+ *  are already fetching; the poll only waits on those. Returns `{ pending, unreferenced }`: `pending`
+ *  = families whose face was STILL `"loading"` when the bound expired (a genuinely stuck fetch, kept
+ *  as a warning); `unreferenced` = faces left `"unloaded"` (declared but no rendered text resolves to
+ *  them — benign, surfaced per-face for an informational log only). Runs entirely inside the browser
+ *  context so it reads the live FontFaceSet. Bounded + state-based ⇒ deterministic (ends on state,
+ *  never on a fixed sleep). `capMs` is a hard ceiling so a hung font request can't stall the render. */
+async function awaitFontsLoaded(
+  page: import("playwright").Page,
+  opts?: { capMs?: number; pollMs?: number },
+): Promise<{ pending: string[]; unreferenced: FontFaceStatus[] }> {
+  const capMs = opts?.capMs ?? 3000;
+  const pollMs = opts?.pollMs ?? 50;
+  try {
+    return await page.evaluate(
+      async ({ capMs, pollMs }) => {
+        const doc = document as Document;
+        const set = doc.fonts as unknown as { ready?: Promise<unknown>; forEach?: (cb: (f: FontFaceStatus) => void) => void } | undefined;
+        if (!set) return { pending: [], unreferenced: [] };
+        const snapshot = (): { family: string; weight: string; style: string; status: string }[] => {
+          const out: { family: string; weight: string; style: string; status: string }[] = [];
+          set.forEach?.((f) => out.push({ family: f.family, weight: f.weight, style: f.style, status: f.status }));
+          return out;
+        };
+        // Only a face still actively fetching is pending; "unloaded" is unreferenced (never fetched).
+        const pending = (faces: { family: string; weight: string; style: string; status: string }[]): string[] => {
+          const p = new Set<string>();
+          for (const f of faces) {
+            if (f.status === "loading") p.add(f.family.replace(/^["']|["']$/g, ""));
+          }
+          return [...p].sort();
+        };
+        // First give the browser's own aggregate signal a chance (bounded — a hung request must not
+        // hold ready forever). Then poll the per-face states until none are loading or the cap expires.
+        await Promise.race([set.ready ?? Promise.resolve(), new Promise((r) => setTimeout(r, capMs))]);
+        const deadline = Date.now() + capMs;
+        // eslint-disable-next-line no-constant-condition
+        while (true) {
+          const faces = snapshot();
+          const left = pending(faces);
+          const done = left.length === 0 || Date.now() >= deadline;
+          if (done) {
+            const unreferenced = faces
+              .filter((f) => f.status === "unloaded")
+              .map((f) => ({ family: f.family.replace(/^["']|["']$/g, ""), weight: f.weight, style: f.style, status: f.status }));
+            return { pending: left, unreferenced };
+          }
+          await new Promise((r) => setTimeout(r, pollMs));
+        }
+      },
+      { capMs, pollMs },
+    ) as { pending: string[]; unreferenced: FontFaceStatus[] };
+  } catch {
+    return { pending: [], unreferenced: [] }; // no FontFaceSet (or an evaluate fault) never blocks the walk
+  }
+}
+
+/** Navigate with `waitUntil:"load"` then wait for a bounded window of network quiet, so
+ *  validation NEVER hard-fails on media that trickles requests. `waitUntil:"networkidle"`
+ *  is a hard timeout: an autoplaying long video (even chunked via 206) keeps issuing bounded
+ *  range fetches, so a strict networkidle can miss its 500ms-idle window and throw at 45s,
+ *  leaving validation reportless. Instead we (1) `goto load` (fires on DOM+subresources, not
+ *  on ongoing media), then (2) poll for `maxQuietMs` of 500ms network silence up to a
+ *  `settleCapMs` ceiling, then proceed regardless. Normal pages reach quiet in well under a
+ *  second, so total time stays comparable; only trickle-media pages spend the extra budget and
+ *  then continue (the video is frame-0-normalized before the screenshot, so determinism holds).
+ *  Returns the goto response (for httpStatus). */
+export async function gotoAndSettle(
+  page: import("playwright").Page,
+  url: string,
+  opts?: { gotoTimeout?: number; settleCapMs?: number; quietMs?: number; pollMs?: number },
+): Promise<import("playwright").Response | null> {
+  const gotoTimeout = opts?.gotoTimeout ?? 45000;
+  const settleCapMs = opts?.settleCapMs ?? 10000;
+  const quietMs = opts?.quietMs ?? 500;
+  const pollMs = opts?.pollMs ?? 500;
+  const resp = await page.goto(url, { waitUntil: "load", timeout: gotoTimeout });
+  // Count in-flight requests so we can detect network quiet without relying on the
+  // strict networkidle heuristic (which throws on trickle-media).
+  let inflight = 0;
+  const onReq = (): void => { inflight++; };
+  const onDone = (): void => { inflight = Math.max(0, inflight - 1); };
+  page.on("request", onReq);
+  page.on("requestfinished", onDone);
+  page.on("requestfailed", onDone);
+  try {
+    const deadline = Date.now() + settleCapMs;
+    let quietSince = inflight === 0 ? Date.now() : 0;
+    while (Date.now() < deadline) {
+      if (inflight === 0) {
+        if (quietSince === 0) quietSince = Date.now();
+        if (Date.now() - quietSince >= quietMs) break; // sustained quiet reached
+      } else {
+        quietSince = 0;
+      }
+      await new Promise((r) => setTimeout(r, pollMs));
+    }
+  } finally {
+    page.off("request", onReq);
+    page.off("requestfinished", onDone);
+    page.off("requestfailed", onDone);
+  }
+  return resp;
+}
+
 async function mapLimit<T, R>(items: T[], limit: number, fn: (item: T, i: number) => Promise<R>): Promise<R[]> {
   const out: R[] = new Array(items.length);
   let next = 0;
@@ -218,6 +430,7 @@ export async function renderApp(opts: {
       const vh = viewportHeight(vw);
       const ctx = await browser.newContext({ ignoreHTTPSErrors: true, viewport: { width: vw, height: vh }, deviceScaleFactor: 1 });
       const runtimeErrors: string[] = [];
+      const fontWarnings: string[] = [];
       const failedResources = new Set<string>();
       let httpStatus = 0;
       try {
@@ -226,9 +439,26 @@ export async function renderApp(opts: {
         page.on("pageerror", (e) => runtimeErrors.push(String(e)));
         page.on("response", (r) => { if (r.status() >= 400) failedResources.add(`${r.status()} ${r.url()}`); });
         page.on("requestfailed", (r) => failedResources.add(`failed ${r.url()}`));
-        const resp = await page.goto(opts.url, { waitUntil: "networkidle", timeout: 45000 });
+        const resp = await gotoAndSettle(page, opts.url);
         if (resp) httpStatus = resp.status();
-        try { await page.evaluate(() => (document as Document).fonts?.ready); } catch { /* ignore */ }
+        // Webfonts must be APPLIED before the DOM walk and the screenshot: a rendered snapshot taken
+        // while the app's @font-face faces are still "unloaded" measures every text box in the
+        // fallback face (systematically narrower/wider glyphs → a bogus size delta attributed to the
+        // clone). Await document.fonts.ready AND poll (bounded, state-based) until every declared face
+        // is terminal, so this holds for both the walk below and the screenshot further down.
+        const { pending: pendingFonts, unreferenced: unrefFaces } = await awaitFontsLoaded(page);
+        if (pendingFonts.length) {
+          const msg = `font-wait: ${pendingFonts.length} @font-face families still loading after wait bound at ${vw}px: ${pendingFonts.join(", ")}`;
+          fontWarnings.push(msg);
+          console.warn(`[render] ${msg}`);
+        }
+        // Declared-but-unreferenced faces (no rendered text resolves to them) are benign — the
+        // browser never fetched them by design. Report them per-face (family+weight+style) as an
+        // informational log only; they are NOT a fidelity warning and never enter fontWarnings.
+        if (unrefFaces.length) {
+          const detail = unrefFaces.map((f) => `${f.family} ${f.weight} ${f.style}`).join(", ");
+          console.log(`[render] font-info: ${unrefFaces.length} declared-but-unreferenced faces at ${vw}px: ${detail}`);
+        }
         // Scroll to settle any lazy effects, then back to top.
         await page.evaluate(async () => {
           const sleep = (ms: number) => new Promise((r) => setTimeout(r, ms));
@@ -255,21 +485,36 @@ export async function renderApp(opts: {
         });
         const snapshot = await page.evaluate(collectPage);
         writeJSONCompact(join(opts.renderedDir, "dom", `dom-${vw}.json`), snapshot);
+        // Screenshot via CDP (captureBeyondViewport, no scroll-stitch) to match the SOURCE
+        // channel exactly — both sides must measure the same at-rest state. Fall back to
+        // Playwright's fullPage stitch if CDP fails. The clone is static so scroll-stitch
+        // matters less here, but symmetric capture is the requirement.
         try {
-          await page.screenshot({ path: join(opts.renderedDir, "screenshots", `${vw}.png`), fullPage: true, timeout: 90_000, animations: "disabled" });
+          const shotPath = join(opts.renderedDir, "screenshots", `${vw}.png`);
+          // Pin every clone-side <video> to frame 0 (paused) before the shot — the SOURCE channel is
+          // now normalized to frame 0 at every viewport too, so both sides show the same frame and a
+          // video's playback time can't manufacture a perceptual diff. (The static clone rarely plays,
+          // but a replayed/autoplaying video would otherwise drift; symmetric normalization is the rule.)
+          await normalizeVideoTime(page);
+          try {
+            await captureFullPageViaCDP(page, shotPath);
+          } catch {
+            await page.screenshot({ path: shotPath, fullPage: true, timeout: 90_000, animations: "disabled" });
+          }
         } catch { /* ignore */ }
-        return { viewport: vw, snapshot, runtimeErrors, failedResources: [...failedResources], httpStatus };
+        return { viewport: vw, snapshot, runtimeErrors, fontWarnings, failedResources: [...failedResources], httpStatus };
       } finally {
         await ctx.close();
       }
     });
     const runtimeErrors = results.flatMap((r) => r.runtimeErrors);
+    const fontWarnings = results.flatMap((r) => r.fontWarnings);
     const failedResources = new Set(results.flatMap((r) => r.failedResources));
     for (const r of results) snapshots[r.viewport] = r.snapshot;
     const non200 = results.find((r) => r.httpStatus && r.httpStatus !== 200);
     const httpStatus = non200?.httpStatus ?? results.find((r) => r.httpStatus)?.httpStatus ?? 0;
     ensureDir(join(opts.renderedDir, "computed"));
-    return { snapshots, runtimeErrors, httpStatus, failedResources: [...failedResources] };
+    return { snapshots, runtimeErrors, httpStatus, failedResources: [...failedResources], fontWarnings };
   } finally {
     await browser.close();
   }
@@ -293,8 +538,10 @@ export async function measureProbeWidths(opts: { url: string; widths: number[] }
         const ctx = await browser.newContext({ ignoreHTTPSErrors: true, viewport: { width: w, height: viewportHeight(w) }, deviceScaleFactor: 1 });
         const page = await ctx.newPage();
         await page.addInitScript(ESBUILD_SHIM);
-        await page.goto(opts.url, { waitUntil: "networkidle", timeout: 45000 });
-        try { await page.evaluate(() => (document as Document).fonts?.ready); } catch { /* ignore */ }
+        await gotoAndSettle(page, opts.url);
+        // This probe walks the DOM and measures text boxes, so — exactly as renderApp does — webfonts
+        // must be applied first, else the probe reads fallback-font widths at the off-band widths.
+        await awaitFontsLoaded(page);
         await page.evaluate(() => {
           const win = window as unknown as { __dittoMotionStopped?: boolean; __dittoMotionStop?: () => void };
           try { win.__dittoMotionStopped = true; } catch { /* ignore */ }
diff --git a/compiler/src/validate/validate.ts b/compiler/src/validate/validate.ts
index 7e173db..8f4c577 100644
--- a/compiler/src/validate/validate.ts
+++ b/compiler/src/validate/validate.ts
@@ -28,6 +28,21 @@ export function probeWidthsFor(viewports: number[]): number[] {
   const widest = sorted[sorted.length - 1] ?? 1920;
   return [...mids, Math.round(widest * 4 / 3)];
 }
+/** True if the URL of an aborted `/assets/` fetch resolves to a real file under the served export.
+ *  Mirrors `serveStatic`'s path mapping (path segment joined onto the served root, `..` stripped) so
+ *  an aborted srcset candidate whose file is present on disk is not mistaken for a 404. A URL we
+ *  cannot parse, or one whose file is absent, is treated as a genuine miss (returns false). */
+export function servedAssetExists(servedRoot: string, url: string): boolean {
+  let pathname: string;
+  try {
+    pathname = new URL(url).pathname;
+  } catch {
+    return false;
+  }
+  const rel = decodeURIComponent(pathname).replace(/^(\.\.[/\\])+/, "").replace(/^\/+/, "");
+  return existsSync(join(servedRoot, rel));
+}
+
 import { buildReport, reportToMarkdown, type Report } from "./report.js";
 import { readJSON, writeJSON, writeText, ensureDir, fileExists } from "../util/fsx.js";
 import type { CaptureResult } from "../capture/capture.js";
@@ -108,6 +123,9 @@ export async function validateRun(runDir: string, opts?: { harnessDir?: string;
     try {
       const r = await renderApp({ url: server.url + "/", viewports, renderedDir });
       snapshots = r.snapshots; runtimeErrors = r.runtimeErrors; httpStatus = r.httpStatus; failedResources = r.failedResources;
+      // Non-fatal: webfonts that never loaded before the render walk (text was measured in a fallback
+      // face). Surfaced as a warning event, NOT a runtime error, so it never fails gate 0.
+      if (r.fontWarnings.length) log({ event: "font_wait_warning", families: r.fontWarnings });
       probeSnaps = await measureProbeWidths({ url: server.url + "/", widths: probeWidthsFor(viewports) });
       if (capture.interaction) {
         interactionGate = await driveInteractionGate({ url: server.url + "/", viewports, ir, interaction: capture.interaction });
@@ -122,16 +140,32 @@ export async function validateRun(runDir: string, opts?: { harnessDir?: string;
         motionGate = await driveMotionGate({ url: server.url + "/", viewports, ir, motion: capture.motion });
         log({ event: "motion_gate", pass: motionGate.pass, metrics: motionGate.metrics });
       }
+    } catch (e) {
+      // A render crash (e.g. a page.goto timeout on trickling media, or a Playwright fault)
+      // must NOT escape reportless — otherwise validation/ stays empty and the run looks
+      // un-validated. Record the error as a runtime error so httpStatus stays 0, gate 0 fails
+      // with a visible issue, and the normal downstream path writes report.json as usual.
+      runtimeErrors.push(`render error: ${e instanceof Error ? e.message : String(e)}`);
+      log({ event: "render_error", error: e instanceof Error ? e.message : String(e) });
     } finally {
       await server.close();
     }
   }
-  // Video/audio elements stream and their requests are aborted ("failed") when the
-  // render snapshot is taken before the stream finishes — the file is materialized,
-  // so this is not an asset failure. Only count non-streaming assets.
-  const assetFailed = failedResources.filter(
-    (f) => f.includes("/assets/") && !/\.(mp4|webm|mov|m4v|ogv|ogg|mp3|wav|m3u8)(\?|$)/i.test(f),
-  );
+  // A generated asset ref is only a real failure if the file it points to is genuinely
+  // missing from the served export. Two aborts are NOT failures even though Chromium logs
+  // them as "failed": (a) video/audio streams aborted when the render snapshot is taken
+  // before the stream finishes; (b) responsive-image <source srcset> candidates whose
+  // in-flight low-priority fetch is aborted when the page closes or the candidate is
+  // re-chosen — the image analogue of (a). So count an /assets/ entry only when it is a
+  // real HTTP >= 400 response, OR a "failed " (aborted) entry whose target file is actually
+  // absent from the served out/ dir. Genuine 404s (file missing) still fail.
+  const assetFailed = failedResources.filter((f) => {
+    if (!f.includes("/assets/")) return false;
+    if (/\.(mp4|webm|mov|m4v|ogv|ogg|mp3|wav|m3u8)(\?|$)/i.test(f)) return false; // streaming media (a)
+    if (!f.startsWith("failed ")) return true; // "<status> <url>" — a real >= 400 response, always count
+    // Aborted fetch (b): excuse it if the file exists under the served export, else it is a real miss.
+    return build.outDir ? !servedAssetExists(build.outDir, f.slice("failed ".length)) : true;
+  });
   const artifactsPresent = ["manifest.json", "sections.json", "tokens.json", "assets.json", "fonts.json"].every((f) => fileExists(join(generatedDir, f)));
   const gate0Issues: string[] = [];
   if (!build.ok) gate0Issues.push("build failed: " + build.stderr.split("\n").filter(Boolean).slice(-3).join(" | "));
diff --git a/compiler/test/bandingFixes.test.ts b/compiler/test/bandingFixes.test.ts
new file mode 100644
index 0000000..4a452fa
--- /dev/null
+++ b/compiler/test/bandingFixes.test.ts
@@ -0,0 +1,232 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import type { IR, IRNode, IRChild, StyleMap, BBox } from "../src/normalize/ir.js";
+import { buildTailwind } from "../src/generate/tailwind.js";
+
+const VPS = [375, 1280];
+const CANONICAL = 1280;
+
+function computed(over: StyleMap = {}): StyleMap {
+  return { display: "block", position: "static", visibility: "visible", listStyleType: "disc", listStylePosition: "outside", ...over };
+}
+
+/** Per-viewport node: distinct computed style per width so a band delta is produced. */
+function pvNode(id: string, tag: string, byVp: Record<number, StyleMap>, children: IRChild[] = [], srcClass?: string): IRNode {
+  const computedByVp: Record<number, StyleMap> = {};
+  const bboxByVp: Record<number, BBox> = {};
+  const visibleByVp: Record<number, boolean> = {};
+  for (const vp of VPS) {
+    computedByVp[vp] = computed(byVp[vp]);
+    bboxByVp[vp] = { x: 0, y: 0, width: vp, height: 100 };
+    visibleByVp[vp] = true;
+  }
+  const n: IRNode = { id, tag, attrs: {}, visibleByVp, bboxByVp, computedByVp, children };
+  if (srcClass) n.srcClass = srcClass;
+  return n;
+}
+
+function irWith(root: IRNode): IR {
+  return {
+    doc: {
+      sourceUrl: "https://example.test/banding",
+      title: "Banding Fixture",
+      lang: "en",
+      charset: "UTF-8",
+      metaViewport: "width=device-width, initial-scale=1",
+      viewports: VPS,
+      sampleViewports: VPS,
+      canonicalViewport: CANONICAL,
+      perViewport: Object.fromEntries(VPS.map((vp) => [vp, { scrollHeight: 800, scrollWidth: vp, htmlBg: "rgb(255, 255, 255)", bodyBg: "rgb(255, 255, 255)", bodyColor: "rgb(0, 0, 0)", bodyFont: "Arial" }])),
+      nodeCount: 3,
+      keyframes: [],
+    },
+    root,
+  };
+}
+
+// C3 — a base RAW value (gradient) with a band that RESETS the same prop to a NON-raw value
+// (`background-image: none` → utility `bg-[none]`) must keep the base gradient in ditto.css, not
+// inline. An inline style out-specifies the @media reset, painting the gradient where the source
+// turned it off (the mobile shimmer-blob defect). The banded-props set must count ALL band-touched
+// props, not just the raw ones.
+describe("buildTailwind banded non-raw override keeps base gradient in ditto.css (C3)", () => {
+  it("does not inline a base gradient when a band resets background-image to none", () => {
+    const grad = "linear-gradient(90deg, rgb(1, 2, 3), rgb(4, 5, 6))";
+    // 1280 (canonical/base): gradient painted; 375 (mobile band): background-image none.
+    const el = pvNode("n1", "span", {
+      375: { backgroundImage: "none" },
+      1280: { backgroundImage: grad },
+    }, [{ text: "Grepping" } as IRChild]);
+    const root = pvNode("n0", "body", { 375: {}, 1280: {} }, [el]);
+    const tw = buildTailwind(irWith(root), new Map());
+    const inline = tw.styleOf.get("n1");
+    const inlineHasGrad = !!inline && [...inline.values()].some((v) => v.includes("gradient("));
+    assert.ok(!inlineHasGrad, `banded gradient must NOT be inlined, got inline: ${inline ? JSON.stringify([...inline]) : "none"}`);
+    // It must instead live in ditto.css (extraCss folded into pseudoCss) as a [data-cid] rule.
+    assert.ok(/\[data-cid="n1"\][\s\S]*gradient\(/.test(tw.pseudoCss), `base gradient must be a ditto.css rule, got:\n${tw.pseudoCss}`);
+  });
+
+  it("still inlines a base gradient with NO band touching background-image (unchanged path)", () => {
+    const grad = "linear-gradient(90deg, rgb(1, 2, 3), rgb(4, 5, 6))";
+    const el = pvNode("n1", "span", {
+      375: { backgroundImage: grad },
+      1280: { backgroundImage: grad },
+    }, [{ text: "static gradient" } as IRChild]);
+    const root = pvNode("n0", "body", { 375: {}, 1280: {} }, [el]);
+    const tw = buildTailwind(irWith(root), new Map());
+    const inline = tw.styleOf.get("n1");
+    const inlineHasGrad = !!inline && [...inline.values()].some((v) => v.includes("gradient("));
+    assert.ok(inlineHasGrad, `a truly static (un-banded) gradient is still inlined, got inline: ${inline ? JSON.stringify([...inline]) : "none"}`);
+  });
+});
+
+// C1 (tailwind intent side) — a variant-only `max-lg:grid-rows-subgrid` covers only a subset of
+// viewports (the axis resolves to explicit tracks at ≥lg). The partial-coverage bail must let subgrid
+// through as a banded variant instead of discarding it.
+describe("buildTailwind partial-coverage subgrid intent (C1)", () => {
+  it("emits grid-rows-subgrid from a variant-only source class", () => {
+    // Grid at both widths; subgrid computed at the mobile band (375) and explicit tracks at 1280.
+    // Source authored `max-lg:grid-rows-subgrid`.
+    const el = pvNode("n1", "div", {
+      375: { display: "grid", gridTemplateRows: "subgrid" },
+      1280: { display: "grid", gridTemplateRows: "340px 340px" },
+    }, [{ text: "card" } as IRChild], "max-lg:grid-rows-subgrid");
+    const root = pvNode("n0", "body", { 375: {}, 1280: {} }, [el]);
+    const tw = buildTailwind(irWith(root), new Map());
+    const cls = tw.classOf.get("n1") || "";
+    assert.ok(/grid-rows-subgrid/.test(cls), `subgrid must survive the partial-intent path, got class: "${cls}"`);
+  });
+});
+
+// FIX 1 (source-intent side) — an authored banded FIXED height (`h-[4rem] md:h-[6.25rem]`) must be
+// recoverable through source intent even though sourceFluidLengthSuffix rejects fixed rem/px lengths.
+// The recovered value is re-emitted as the CAPTURED computed px (root-font-size independent), and the
+// generated `h-full`/`h-auto` on that axis is dropped in its favour.
+describe("buildTailwind recovers authored banded fixed height as computed px (FIX 1)", () => {
+  // A per-vp node with distinct computed height + matching bbox on each axis, so geometry corroborates.
+  function fixedHNode(id: string, tag: string, hByVp: Record<number, number>, srcClass: string): IRNode {
+    const computedByVp: Record<number, StyleMap> = {};
+    const bboxByVp: Record<number, BBox> = {};
+    const visibleByVp: Record<number, boolean> = {};
+    for (const vp of VPS) {
+      computedByVp[vp] = computed({ display: "flex", height: `${hByVp[vp]}px` });
+      bboxByVp[vp] = { x: 0, y: 0, width: vp, height: hByVp[vp]! };
+      visibleByVp[vp] = true;
+    }
+    const n: IRNode = { id, tag, attrs: {}, visibleByVp, bboxByVp, computedByVp, children: [] };
+    n.srcClass = srcClass;
+    // Probe reads the fill↔content cycle (a grid/flex item whose child fills it): hAuto:false but
+    // hFill:true, so the generator would otherwise emit h-full. Source intent must still recover.
+    n.sizingByVp = Object.fromEntries(VPS.map((vp) => [vp, { wAuto: false, wFill: true, hAuto: false, hFill: true }]));
+    return n;
+  }
+
+  it("emits banded computed px (h-[60px]/h-[100px]) and no h-full", () => {
+    // Source authors `h-[4rem]` (base) and `md:h-[6.25rem]`; the source root is 15px so 4rem→60px @375
+    // and 6.25rem→100px @1280. Emitted as px so the clone's root font-size can't mis-size it.
+    const el = fixedHNode("n1", "div", { 375: 60, 1280: 100 }, "flex h-[4rem] w-full md:h-[6.25rem]");
+    const root = pvNode("n0", "body", { 375: {}, 1280: {} }, [el]);
+    const tw = buildTailwind(irWith(root), new Map());
+    const cls = tw.classOf.get("n1") || "";
+    assert.ok(!/\bh-full\b/.test(cls), `authored fixed height must not stay h-full, got class: "${cls}"`);
+    // The captured px must appear (as an arbitrary px value or a clean rem token equivalent). Accept the
+    // px form or its 16px-root rem equivalent (100px→6.25rem, 60px→3.75rem) since the pretty-printer may
+    // fold clean px back to rem — both resolve to the captured px at the clone's 16px root.
+    assert.ok(/h-\[100px\]|h-\[6\.25rem\]/.test(cls), `desktop height (100px/6.25rem@16root) must appear, got class: "${cls}"`);
+    assert.ok(/h-\[60px\]|h-\[3\.75rem\]/.test(cls), `mobile height (60px/3.75rem@16root) must appear, got class: "${cls}"`);
+  });
+});
+
+// FIX 2 (source-intent named-token validation) — a source built on an OLDER Tailwind authored
+// `max-w-md`, whose scale resolved `md` to 640px; the clone's Tailwind v4 resolves `max-w-md` to
+// 448px. Re-emitting the name verbatim silently re-sizes the box (640→448). The source-intent pass
+// must validate the modern named-token px against the captured computed px and, on mismatch, emit
+// the captured px as an arbitrary value instead of the mis-resolving name.
+describe("buildTailwind validates named length tokens against captured px (FIX 2)", () => {
+  // A max-width node whose computed maxWidth is `capPx` at every viewport, carrying `srcClass`.
+  function maxWNode(capPx: number, srcClass: string): IRNode {
+    const computedByVp: Record<number, StyleMap> = {};
+    const bboxByVp: Record<number, BBox> = {};
+    const visibleByVp: Record<number, boolean> = {};
+    for (const vp of VPS) {
+      computedByVp[vp] = computed({ maxWidth: `${capPx}px` });
+      bboxByVp[vp] = { x: 0, y: 0, width: Math.min(vp, capPx), height: 100 };
+      visibleByVp[vp] = true;
+    }
+    const n: IRNode = { id: "n1", tag: "div", attrs: {}, visibleByVp, bboxByVp, computedByVp, children: [{ text: "col" } as IRChild] };
+    n.srcClass = srcClass;
+    return n;
+  }
+
+  it("re-emits max-w-md as the captured px when the modern token value disagrees (640 ≠ 448)", () => {
+    // Modern max-w-md = 28rem = 448px, but the source computed a 640px cap → arbitrary px, not the name.
+    const el = maxWNode(640, "max-w-md");
+    const root = pvNode("n0", "body", { 375: {}, 1280: {} }, [el]);
+    const tw = buildTailwind(irWith(root), new Map());
+    const cls = tw.classOf.get("n1") || "";
+    assert.ok(!/\bmax-w-md\b/.test(cls), `mis-resolving max-w-md name must not survive, got class: "${cls}"`);
+    assert.ok(/max-w-\[640px\]|max-w-\[40rem\]/.test(cls), `captured 640px cap must be emitted arbitrarily, got class: "${cls}"`);
+  });
+
+  it("keeps max-w-lg verbatim when the modern token value matches the captured px (512 == 512)", () => {
+    // Modern max-w-lg = 32rem = 512px, and the source computed a 512px cap → the authored name is faithful.
+    const el = maxWNode(512, "max-w-lg");
+    const root = pvNode("n0", "body", { 375: {}, 1280: {} }, [el]);
+    const tw = buildTailwind(irWith(root), new Map());
+    const cls = tw.classOf.get("n1") || "";
+    assert.ok(/\bmax-w-lg\b/.test(cls), `matching max-w-lg name must survive, got class: "${cls}"`);
+    assert.ok(!/max-w-\[/.test(cls), `no arbitrary max-w should be emitted when the name matches, got class: "${cls}"`);
+  });
+});
+
+// FIX 3 (source-intent breakpoint specificity) — an authored gallery grid
+// `grid-cols-1 md:grid-cols-2 lg:grid-cols-3` (both `md:` and `lg:` are min-width variants, so BOTH
+// are active at 1280). Tailwind emits its rules sorted by breakpoint, so `lg:` wins there — the base
+// (canonical=1280) is grid-cols-3. Choosing the LAST active token in class-attribute order instead
+// (`… lg:grid-cols-3 md:grid-cols-2`) wrongly takes md's grid-cols-2 as base and drops the desktop
+// grid-cols-3 band entirely. The pass must pick the highest-min-width active variant per viewport.
+describe("buildTailwind source-intent picks the highest active breakpoint per viewport (FIX 3)", () => {
+  const GVPS = [375, 768, 1280, 1920];
+  function gridIr(srcClass: string): IR {
+    const gtc: Record<number, string> = {
+      375: "343px", 768: "348px 348px",
+      1280: "346.66px 346.66px 346.66px", 1920: "346.66px 346.66px 346.66px",
+    };
+    const gridW: Record<number, number> = { 375: 343, 768: 720, 1280: 1064, 1920: 1064 };
+    const mk = (id: string, byVp: Record<number, StyleMap>, w: Record<number, number>, kids: IRChild[] = [], sc?: string): IRNode => {
+      const computedByVp: Record<number, StyleMap> = {};
+      const bboxByVp: Record<number, BBox> = {};
+      const visibleByVp: Record<number, boolean> = {};
+      for (const vp of GVPS) {
+        computedByVp[vp] = computed(byVp[vp]);
+        bboxByVp[vp] = { x: 0, y: 0, width: w[vp]!, height: 100 };
+        visibleByVp[vp] = true;
+      }
+      const n: IRNode = { id, tag: "div", attrs: {}, visibleByVp, bboxByVp, computedByVp, children: kids };
+      if (sc) n.srcClass = sc;
+      return n;
+    };
+    const items = [0, 1, 2].map((i) => mk(`c${i}`, Object.fromEntries(GVPS.map((vp) => [vp, { display: "block" }])), Object.fromEntries(GVPS.map((vp) => [vp, 340])), [{ text: "x" } as IRChild]));
+    const grid = mk("n123", Object.fromEntries(GVPS.map((vp) => [vp, { display: "grid", gridTemplateColumns: gtc[vp], columnGap: "24px", rowGap: "24px", gap: "24px" }])), gridW, items, srcClass);
+    const root = mk("n0", Object.fromEntries(GVPS.map((vp) => [vp, {}])), Object.fromEntries(GVPS.map((vp) => [vp, vp])), [grid]);
+    return {
+      doc: {
+        sourceUrl: "https://example.test/grid", title: "Grid", lang: "en", charset: "UTF-8",
+        metaViewport: "width=device-width, initial-scale=1", viewports: GVPS, sampleViewports: GVPS, canonicalViewport: 1280,
+        perViewport: Object.fromEntries(GVPS.map((vp) => [vp, { scrollHeight: 800, scrollWidth: vp, htmlBg: "rgb(255, 255, 255)", bodyBg: "rgb(255, 255, 255)", bodyColor: "rgb(0, 0, 0)", bodyFont: "Arial" }])),
+        nodeCount: 5, keyframes: [],
+      },
+      root,
+    };
+  }
+
+  it("emits base grid-cols-3 (lg wins at 1280) even when md: follows lg: in the class string", () => {
+    const tw = buildTailwind(gridIr("grid grid-cols-1 gap-6 lg:grid-cols-3 md:grid-cols-2"), new Map());
+    const cls = tw.classOf.get("n123") || "";
+    const toks = cls.split(/\s+/);
+    assert.ok(toks.includes("grid-cols-3"), `desktop base must be grid-cols-3 (lg wins at 1280), got class: "${cls}"`);
+    assert.ok(!toks.some((t) => /(?:^|:)grid-cols-2$/.test(t) && !t.includes("md:max-lg:")), `md's grid-cols-2 must not become the base, got class: "${cls}"`);
+    assert.ok(toks.includes("md:max-lg:grid-cols-2"), `tablet band must be grid-cols-2, got class: "${cls}"`);
+    assert.ok(toks.includes("max-md:grid-cols-1"), `mobile band must be grid-cols-1, got class: "${cls}"`);
+  });
+});
diff --git a/compiler/test/canvasStill.test.ts b/compiler/test/canvasStill.test.ts
new file mode 100644
index 0000000..bd40517
--- /dev/null
+++ b/compiler/test/canvasStill.test.ts
@@ -0,0 +1,108 @@
+import { describe, it, before, after } from "node:test";
+import assert from "node:assert/strict";
+import { chromium, type Browser, type Page } from "playwright";
+import { captureCanvasStillsInPage } from "../src/capture/capture.js";
+import type { IRNode, IRChild, StyleMap, BBox } from "../src/normalize/ir.js";
+import { propsList, resolveTag, renderChildrenJsx } from "../src/generate/app.js";
+
+// tsx/esbuild wraps functions with a __name() helper for stack traces; the serialized
+// page functions carry those calls, so shim it (same as capture.ts's init script).
+const ESBUILD_SHIM =
+  "globalThis.__name = globalThis.__name || ((fn) => fn);" +
+  "globalThis.__defProp = globalThis.__defProp || Object.defineProperty;";
+
+describe("capture: canvas raster fallback (in-page)", () => {
+  let browser: Browser;
+  let page: Page;
+  before(async () => {
+    browser = await chromium.launch();
+    page = await browser.newPage();
+    await page.addInitScript(ESBUILD_SHIM);
+    await page.setContent(`
+      <canvas id="big" width="200" height="100"></canvas>
+      <canvas id="tiny" width="20" height="20"></canvas>
+      <canvas id="ghost" width="300" height="150" style="visibility:hidden"></canvas>
+      <script>
+        const ctx = document.getElementById("big").getContext("2d");
+        ctx.fillStyle = "#3b82f6";
+        ctx.fillRect(10, 10, 180, 80);
+      </script>
+    `);
+    // setContent replaces the document without a navigation, so the init script may
+    // not have applied — evaluate the shim directly (same as capture.ts's frame path).
+    await page.evaluate(ESBUILD_SHIM);
+  });
+  after(async () => {
+    await browser.close();
+  });
+
+  it("rasterizes a meaningful 2D canvas to a PNG data URL under a synthetic clone-canvas URL", async () => {
+    const plan = await page.evaluate(captureCanvasStillsInPage);
+    assert.equal(plan.stills.length, 1, "exactly one canvas qualifies");
+    assert.equal(plan.shots.length, 0, "readable 2D canvas needs no element-screenshot fallback");
+    const still = plan.stills[0]!;
+    assert.ok(still.dataUrl.startsWith("data:image/png"), `PNG data URL (got ${still.dataUrl.slice(0, 30)})`);
+    assert.match(still.url, /^https:\/\/clone-canvas\.local\/0-[0-9a-z]+\.png$/);
+    assert.equal(still.sel, 'canvas[data-clone-canvas="0"]');
+    const bytes = Buffer.from(still.dataUrl.slice(still.dataUrl.indexOf(",") + 1), "base64");
+    assert.ok(bytes.length > 0, "still decodes to non-empty bytes");
+
+    const stamped = await page.evaluate(() => ({
+      big: document.getElementById("big")?.getAttribute("data-clone-canvas") ?? null,
+      tiny: document.getElementById("tiny")?.getAttribute("data-clone-canvas") ?? null,
+      ghost: document.getElementById("ghost")?.getAttribute("data-clone-canvas") ?? null,
+    }));
+    assert.equal(stamped.big, "0", "qualifying canvas gets the stable marker");
+    assert.equal(stamped.tiny, null, "a 20x20 canvas is below the meaningful-size gate");
+    assert.equal(stamped.ghost, null, "a hidden canvas is skipped");
+  });
+});
+
+const VPS = [375, 1280];
+const SOURCE = "https://example.test/page";
+const GIF = "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7";
+
+function el(id: string, tag: string, attrs: Record<string, string> = {}, children: IRChild[] = [], visible = true): IRNode {
+  const computedByVp: Record<number, StyleMap> = {};
+  const bboxByVp: Record<number, BBox> = {};
+  const visibleByVp: Record<number, boolean> = {};
+  for (const vp of VPS) {
+    computedByVp[vp] = { display: "block", position: "static", visibility: "visible" };
+    bboxByVp[vp] = { x: 0, y: 0, width: visible ? 640 : 0, height: visible ? 360 : 0 };
+    visibleByVp[vp] = visible;
+  }
+  return { id, tag, attrs, visibleByVp, bboxByVp, computedByVp, children };
+}
+
+describe("generate: canvas-still emission", () => {
+  const STILL_URL = "https://clone-canvas.local/0-abc.png";
+  const LOCAL = "/assets/cloned/images/ab.png";
+  const assetMap = new Map([[STILL_URL, LOCAL]]);
+  const canvas = () => el("7", "canvas", { src: STILL_URL, width: "200", height: "100" });
+
+  it("retags a canvas carrying a captured still to <img>; a bare canvas stays canvas", () => {
+    assert.equal(resolveTag(canvas(), false), "img");
+    assert.equal(resolveTag(el("8", "canvas", { width: "200", height: "100" }), false), "canvas");
+  });
+
+  it("resolves the synthetic still URL through the asset map and emits data-cid + alt", () => {
+    const p = new Map(propsList(canvas(), assetMap, SOURCE));
+    assert.equal(p.get("src"), JSON.stringify(LOCAL));
+    assert.equal(p.get('"data-cid"'), JSON.stringify("7"));
+    assert.equal(p.get("alt"), JSON.stringify(""), "decorative alt is injected for the raster still");
+    assert.equal(p.get("width"), JSON.stringify("200"));
+    assert.equal(p.get("height"), JSON.stringify("100"));
+  });
+
+  it("renders a self-closing <img> in place of the canvas", () => {
+    const jsx = renderChildrenJsx([canvas()], assetMap, SOURCE, 0);
+    assert.match(jsx, /<img[^>]*data-cid="7"[^>]*\/>/);
+    assert.match(jsx, new RegExp(`src="${LOCAL.replace(/[/]/g, "\\/")}"`));
+    assert.ok(!jsx.includes("<canvas"), "no canvas element remains");
+  });
+
+  it("falls back to the transparent GIF when the still missed the asset map (never a remote URL)", () => {
+    const p = new Map(propsList(canvas(), new Map(), SOURCE));
+    assert.equal(p.get("src"), JSON.stringify(GIF));
+  });
+});
diff --git a/compiler/test/cdpScreenshot.test.ts b/compiler/test/cdpScreenshot.test.ts
new file mode 100644
index 0000000..4321625
--- /dev/null
+++ b/compiler/test/cdpScreenshot.test.ts
@@ -0,0 +1,84 @@
+import { describe, it, before, after } from "node:test";
+import assert from "node:assert/strict";
+import { join, dirname } from "node:path";
+import { fileURLToPath } from "node:url";
+import { mkdtempSync, readFileSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { chromium, type Browser, type Page } from "playwright";
+import { PNG } from "pngjs";
+import pixelmatch from "pixelmatch";
+import { captureFullPageViaCDP } from "../src/capture/capture.js";
+
+const ESBUILD_SHIM = "globalThis.__name = globalThis.__name || ((fn) => fn);";
+
+// A STATIC page (no scroll-linked animation) several viewports tall: a few full-width
+// colored bands. Both capture paths should render the identical at-rest picture, so any
+// difference is purely a capture-mechanism artifact (scrollbar gutter, off-by-one), which
+// is exactly what this test measures.
+const BANDS_HTML =
+  "<!doctype html><html><head><style>" +
+  "*{margin:0;padding:0;box-sizing:border-box}" +
+  "html,body{width:100%}" +
+  ".band{width:100%;height:600px;display:flex;align-items:center;justify-content:center;" +
+  "font:bold 48px sans-serif;color:#fff}" +
+  ".b0{background:#c0392b}.b1{background:#27ae60}.b2{background:#2980b9}" +
+  ".b3{background:#8e44ad}.b4{background:#d35400}" +
+  "</style></head><body>" +
+  "<div class='band b0'>1</div><div class='band b1'>2</div>" +
+  "<div class='band b2'>3</div><div class='band b3'>4</div>" +
+  "<div class='band b4'>5</div>" +
+  "</body></html>";
+
+describe("CDP full-page capture vs Playwright fullPage stitch (static fixture)", () => {
+  let browser: Browser;
+  let page: Page;
+  let tmp: string;
+
+  before(async () => {
+    browser = await chromium.launch({ args: ["--disable-dev-shm-usage"] });
+    // A viewport SHORTER than the content so fullPage must span multiple bands: this is
+    // where Playwright would scroll-stitch and CDP renders in one shot.
+    const context = await browser.newContext({ viewport: { width: 800, height: 700 }, deviceScaleFactor: 1 });
+    page = await context.newPage();
+    await page.addInitScript(ESBUILD_SHIM);
+    await page.setContent(BANDS_HTML, { waitUntil: "load" });
+    tmp = mkdtempSync(join(tmpdir(), "cdp-shot-"));
+  });
+
+  after(async () => {
+    await browser.close();
+    if (tmp) rmSync(tmp, { recursive: true, force: true });
+  });
+
+  it("produces a valid PNG of the full content height (not just the viewport)", async () => {
+    const cdpPath = join(tmp, "cdp.png");
+    await captureFullPageViaCDP(page, cdpPath);
+    const cdp = PNG.sync.read(readFileSync(cdpPath));
+    // 5 bands * 600px = 3000px tall, well beyond the 700px viewport.
+    assert.ok(cdp.height >= 2900, `CDP shot spans full content (got ${cdp.height})`);
+    assert.ok(cdp.width >= 780 && cdp.width <= 800, `CDP width ~= content width (got ${cdp.width})`);
+    assert.ok(readFileSync(cdpPath).length > 1000, "CDP PNG is non-trivial in size");
+  });
+
+  it("is pixel-equivalent to Playwright's fullPage screenshot on a static page", async () => {
+    const cdpPath = join(tmp, "cdp2.png");
+    const pwPath = join(tmp, "pw.png");
+    await captureFullPageViaCDP(page, cdpPath);
+    await page.screenshot({ path: pwPath, fullPage: true, animations: "disabled" });
+
+    const cdp = PNG.sync.read(readFileSync(cdpPath));
+    const pw = PNG.sync.read(readFileSync(pwPath));
+
+    // Dimensions must match (a scrollbar-gutter difference would show up here first).
+    assert.equal(cdp.width, pw.width, `width match (cdp ${cdp.width} vs pw ${pw.width})`);
+    assert.equal(cdp.height, pw.height, `height match (cdp ${cdp.height} vs pw ${pw.height})`);
+
+    const { width, height } = cdp;
+    const diff = new PNG({ width, height });
+    const mismatched = pixelmatch(cdp.data, pw.data, diff.data, width, height, { threshold: 0.1 });
+    const pct = (mismatched / (width * height)) * 100;
+    // On a static page the two mechanisms should be near-identical. Allow a tiny tolerance
+    // for antialiasing at band seams; assert well under 0.5% differing pixels.
+    assert.ok(pct < 0.5, `pixel delta ${pct.toFixed(4)}% (${mismatched} px) must be < 0.5%`);
+  });
+});
diff --git a/compiler/test/codegenHygiene.test.ts b/compiler/test/codegenHygiene.test.ts
new file mode 100644
index 0000000..0d447d7
--- /dev/null
+++ b/compiler/test/codegenHygiene.test.ts
@@ -0,0 +1,199 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import type { IR, IRNode, IRChild, StyleMap, BBox } from "../src/normalize/ir.js";
+import {
+  CN_UTILS_MODULE,
+  cnImportLine,
+  componentFiles,
+  generatePageTsx,
+  injectLottieDep,
+  PACKAGE_JSON,
+  PACKAGE_JSON_TW,
+  PACKAGE_JSON_VITE,
+  PACKAGE_JSON_VITE_TW,
+  propsList,
+  type ComponentRegistry,
+} from "../src/generate/app.js";
+import { DITTO_WIRE_TSX, ACCORDION_TSX } from "../src/generate/interactive.js";
+import { DROPDOWN_MENU_TSX } from "../src/generate/menu.js";
+import { declToUtil, snapLen } from "../src/generate/tailwind.js";
+
+const VPS = [1280];
+const CANONICAL = 1280;
+
+function computed(over: StyleMap = {}): StyleMap {
+  return { display: "block", position: "static", visibility: "visible", whiteSpace: "normal", ...over };
+}
+
+function node(id: string, tag: string, cs: StyleMap, children: IRChild[] = []): IRNode {
+  const computedByVp: Record<number, StyleMap> = {};
+  const bboxByVp: Record<number, BBox> = {};
+  const visibleByVp: Record<number, boolean> = {};
+  for (const vp of VPS) {
+    computedByVp[vp] = { ...cs };
+    bboxByVp[vp] = { x: 0, y: 0, width: vp, height: 100 };
+    visibleByVp[vp] = true;
+  }
+  return { id, tag, attrs: {}, visibleByVp, bboxByVp, computedByVp, children };
+}
+
+function irWith(root: IRNode): IR {
+  return {
+    doc: {
+      sourceUrl: "https://example.test/",
+      title: "Fixture",
+      lang: "en",
+      charset: "UTF-8",
+      metaViewport: "width=device-width, initial-scale=1",
+      viewports: VPS,
+      sampleViewports: VPS,
+      canonicalViewport: CANONICAL,
+      perViewport: Object.fromEntries(VPS.map((vp) => [vp, { scrollHeight: 800, scrollWidth: vp, htmlBg: "rgb(255, 255, 255)", bodyBg: "rgb(255, 255, 255)", bodyColor: "rgb(0, 0, 0)", bodyFont: "Arial" }])),
+      nodeCount: 4,
+      keyframes: [],
+    },
+    root,
+  };
+}
+
+// ---- Fix 1: emitted runtime components clean up their listeners ----
+describe("runtime components abort their listeners on unmount (fix 1)", () => {
+  const templates: Array<[string, string]> = [
+    ["DittoWire", DITTO_WIRE_TSX],
+    ["Accordion", ACCORDION_TSX],
+    ["DropdownMenu", DROPDOWN_MENU_TSX],
+  ];
+  for (const [name, tsx] of templates) {
+    it(`${name}: one AbortController, every addEventListener signalled, cleanup returns abort`, () => {
+      assert.ok(tsx.includes("new AbortController()"), "creates an AbortController");
+      assert.ok(tsx.includes("ac.abort()"), "effect cleanup aborts");
+      // Every addEventListener must carry a listener-options object with the signal (either
+      // `, { signal })` or `, { passive: true, signal })`). Count-match guarantees none is missed.
+      const adds = (tsx.match(/addEventListener\(/g) ?? []).length;
+      const signalled = (tsx.match(/, \{ signal \}\)/g) ?? []).length
+        + (tsx.match(/, \{ passive: true, signal \}\)/g) ?? []).length;
+      assert.ok(adds > 0, "has listeners");
+      assert.equal(signalled, adds, "every addEventListener passes the abort signal");
+      // The stale re-wire guard is gone; effects are idempotent + cleaned up instead.
+      assert.ok(!tsx.includes("wired.current"), "no wired.current guard");
+    });
+  }
+
+  it("DropdownMenu removes any still-open panels on unmount", () => {
+    assert.ok(DROPDOWN_MENU_TSX.includes("openPanels"), "tracks open panels");
+    assert.ok(DROPDOWN_MENU_TSX.includes("openPanels.splice(0)) p.remove()"), "removes panels on cleanup");
+  });
+});
+
+// ---- Fix 2: cn() is a single shared module, imported (not copied per file) ----
+describe("cn() is deduplicated into src/lib/utils (fix 2)", () => {
+  it("exports a single cn from the shared utils module", () => {
+    assert.ok(CN_UTILS_MODULE.includes("export function cn("), "utils module exports cn");
+  });
+
+  it("cnImportLine resolves to the shared module at the right depth", () => {
+    assert.equal(cnImportLine(1), 'import { cn } from "../lib/utils";');
+    assert.equal(cnImportLine(2), 'import { cn } from "../../lib/utils";');
+  });
+
+  it("a component module that uses cn() imports it rather than redefining it", () => {
+    // componentFiles reads only funcDefs / byName / fieldTypes / dataDecls / styleDecls.
+    const reg = {
+      byName: new Map([["Card", { runs: 1, instances: 2, cids: ["n1"] }]]),
+      funcDefs: new Map([["Card", 'function Card({ styles }: { styles: string }) {\n  return <div className={cn("p-4", styles)} />;\n}']]),
+      fieldTypes: new Map(),
+      dataDecls: [],
+      cidDecls: [],
+      styleDecls: [],
+    } as unknown as ComponentRegistry;
+    const files = componentFiles(reg);
+    const card = files.find((f) => f.name === "Card")!.module;
+    assert.ok(card.includes('import { cn } from "../../lib/utils";'), "imports shared cn");
+    assert.ok(!card.includes("function cn("), "no inline cn definition");
+  });
+});
+
+// ---- Fix 3: JSX whitespace is collapsed under white-space: normal ----
+describe("JSX whitespace collapses under white-space:normal (fix 3)", () => {
+  it("collapses captured \\n\\t indentation and multi-space runs to single spaces", () => {
+    const p = node("n1", "p", computed(), [{ text: "\n\t\tSkip to content\n\t\t" }]);
+    const root = node("n0", "body", computed(), [p]);
+    const tsx = generatePageTsx(irWith(root), new Map(), "https://example.test/");
+    assert.ok(!/\{"[^"]*\\n[^"]*"\}/.test(tsx), "no literal \\n frozen in text");
+    assert.ok(!/\{"\s{2,}"\}/.test(tsx), "no multi-space whitespace literal");
+    assert.ok(tsx.includes("Skip to content"), "content preserved");
+  });
+
+  it("preserves whitespace verbatim inside a <pre> (white-space: pre)", () => {
+    const pre = node("n1", "pre", computed({ whiteSpace: "pre" }), [{ text: "line1\n\tline2" }]);
+    const root = node("n0", "body", computed(), [pre]);
+    const tsx = generatePageTsx(irWith(root), new Map(), "https://example.test/");
+    assert.ok(tsx.includes("line1\\n\\tline2"), "pre keeps raw newlines/tabs");
+  });
+});
+
+// ---- Fix 5: sub-pixel arbitrary values snap ----
+describe("sub-pixel lengths snap (fix 5)", () => {
+  it("snapLen keeps genuine fractions at 1 decimal, snaps near-integer jitter to an integer", () => {
+    assert.equal(snapLen("204.797px"), "204.8px");
+    assert.equal(snapLen("627.188px"), "627.2px");
+    assert.equal(snapLen("100.3px"), "100.3px");
+    assert.equal(snapLen("204.98px"), "205px"); // within 0.1px of an integer → snap
+    assert.equal(snapLen("2.996px"), "3px"); // rem/px jitter snaps
+    assert.equal(snapLen("627px"), "627px"); // already clean
+  });
+
+  it("snapLen leaves non-simple values (calc/percent/multi-token) untouched", () => {
+    assert.equal(snapLen("calc(100% - 3.333px)"), "calc(100% - 3.333px)");
+    assert.equal(snapLen("50.5%"), "50.5%");
+    assert.equal(snapLen("0px 2.5px"), "0px 2.5px");
+  });
+
+  it("declToUtil snaps a width arbitrary value but keeps border-width exact", () => {
+    assert.equal(declToUtil("width", "204.797px"), "w-[204.8px]");
+    // Border width sub-pixel precision is load-bearing — left untouched.
+    assert.equal(declToUtil("border-width", "0.667px"), "border-[0.667px]");
+  });
+});
+
+// ---- Fix 7: every emitted runtime import is a declared dependency ----
+describe("lottie-web is declared when its import is emitted (fix 7)", () => {
+  it("injectLottieDep pins lottie-web into every package.json template", () => {
+    for (const pkg of [PACKAGE_JSON, PACKAGE_JSON_TW, PACKAGE_JSON_VITE, PACKAGE_JSON_VITE_TW]) {
+      const injected = injectLottieDep(pkg);
+      const deps = JSON.parse(injected).dependencies as Record<string, string>;
+      assert.equal(deps["lottie-web"], "5.12.2", "lottie-web pinned to the harness version");
+    }
+  });
+});
+
+// ---- FIX 5: javascript: hrefs are sanitized to an inert '#' ----
+// React refuses to render a `javascript:*` href verbatim — it rewrites it to a long
+// `javascript:throw new Error('React has blocked a javascript: URL…')` string that no longer matches
+// the source href in the link gate. Emit an inert `#` instead (the script behaviour isn't reproduced).
+describe("javascript: hrefs are emitted as an inert '#' (FIX 5)", () => {
+  const hrefOf = (n: IRNode): string | undefined => {
+    const p = propsList(n, new Map(), "https://example.test/").find(([k]) => k === "href");
+    return p ? JSON.parse(p[1]) : undefined;
+  };
+  it("rewrites a javascript: href to #", () => {
+    const a = node("n1", "a", computed());
+    a.attrs = { href: "Javascript:{}" };
+    assert.equal(hrefOf(a), "#", "a javascript: href is sanitized to #");
+  });
+  it("rewrites javascript:void(0) too (case-insensitive, with args)", () => {
+    const a = node("n1", "a", computed());
+    a.attrs = { href: "javascript:void(0)" };
+    assert.equal(hrefOf(a), "#");
+  });
+  it("leaves a normal in-page anchor href untouched", () => {
+    const a = node("n1", "a", computed());
+    a.attrs = { href: "#section" };
+    assert.equal(hrefOf(a), "#section", "a real fragment link is preserved");
+  });
+  it("leaves an ordinary external href resolved (not collapsed to #)", () => {
+    const a = node("n1", "a", computed());
+    a.attrs = { href: "https://example.test/products" };
+    assert.equal(hrefOf(a), "https://example.test/products");
+  });
+});
diff --git a/compiler/test/css.test.ts b/compiler/test/css.test.ts
index 8a9b293..9458cb1 100644
--- a/compiler/test/css.test.ts
+++ b/compiler/test/css.test.ts
@@ -1,7 +1,8 @@
 import { describe, it } from "node:test";
 import assert from "node:assert/strict";
 import type { IR, IRNode, IRChild, StyleMap, BBox } from "../src/normalize/ir.js";
-import { generateCss } from "../src/generate/css.js";
+import type { RawSizing } from "../src/capture/walker.js";
+import { generateCss, collectNodeRules, RESET_CSS } from "../src/generate/css.js";
 
 const VPS = [375, 1280];
 const CANONICAL = 1280;
@@ -48,6 +49,42 @@ function baseRule(css: string, id: string): string {
   return m?.[1] ?? "";
 }
 
+// Root scroll-lock un-clamp: a popup vendor locks the page with
+// body{position:absolute;overflow:hidden;height:100vh}, which the capture bakes as the body's
+// computed style AND collapses document.scrollHeight down to the clamp (so the captured-scrollHeight
+// trigger can never fire). The IR's in-flow CONTENT EXTENT (a footer laid out at y=5000) still
+// exceeds the clamp, so the un-clamp must fire off that signal and strip the lock.
+describe("generateCss root scroll-lock un-clamp (content-extent trigger)", () => {
+  it("drops the body height/position/overflow lock when IR content extent exceeds the clamp", () => {
+    const footer = node("n1", "footer", computed());
+    // Footer sits far below the one-viewport clamp at every viewport.
+    for (const vp of VPS) footer.bboxByVp[vp] = { x: 0, y: 4000, width: vp, height: 1000 }; // bottom = 5000
+    const bodyCs = computed({ position: "absolute", overflow: "hidden", overflowY: "hidden", height: "812px", top: "0px", left: "0px" });
+    const root = node("n0", "body", bodyCs, [footer]);
+    for (const vp of VPS) root.bboxByVp[vp] = { x: 0, y: 0, width: vp, height: 812 };
+    // perViewport.scrollHeight stays collapsed to 800 (the lock's doing) — so ONLY the content
+    // extent can trigger the un-clamp.
+    const css = generateCss(irWith(root), new Map());
+    const body = baseRule(css, "n0");
+    assert.ok(!/height:812px/.test(body), `body height clamp dropped (got: ${body})`);
+    assert.ok(!/position:absolute/.test(body), `body position:absolute stripped (got: ${body})`);
+    assert.ok(/overflow-y:visible/.test(body), `overflow-y forced visible (got: ${body})`);
+    assert.ok(!/overflow:hidden/.test(body), `overflow:hidden not emitted (got: ${body})`);
+  });
+
+  it("does NOT un-clamp a genuine one-screen page (content extent within the clamp)", () => {
+    const inner = node("n1", "div", computed());
+    for (const vp of VPS) inner.bboxByVp[vp] = { x: 0, y: 0, width: vp, height: 700 };
+    const bodyCs = computed({ overflow: "hidden", overflowY: "hidden", height: "800px" });
+    const root = node("n0", "body", bodyCs, [inner]);
+    for (const vp of VPS) root.bboxByVp[vp] = { x: 0, y: 0, width: vp, height: 800 };
+    const css = generateCss(irWith(root), new Map());
+    const body = baseRule(css, "n0");
+    // The clamp is legitimate (content fits) — height kept, overflow not forced to visible.
+    assert.ok(/height:800px/.test(body), `legit body height preserved (got: ${body})`);
+  });
+});
+
 describe("generateCss list markers", () => {
   it("re-establishes list-style on a <ul> whose disc equals the parent's initial value", () => {
     // list-style-type's initial value is `disc` on EVERY element, so a real <ul disc>
@@ -232,6 +269,31 @@ describe("generateCss hidden-node banded geometry", () => {
     assert.ok(mobile.includes("visibility:hidden"), `child should carry the hide, got: ${mobile}`);
     assert.ok(!mobile.includes("left:10px"), `ancestor-hidden child must not emit geometry, got: ${mobile}`);
   });
+
+  it("emits per-band geometry for an occupying slide off-viewport at EVERY width, base included", () => {
+    // A carousel slide 6–12: a shrink-0 flex item off-screen RIGHT at every captured width — 375,
+    // the 1280 canonical base, AND 1920 — so it is never ownHidden, never ancestor-hidden, and never
+    // visibleByVp[base]=true (the walker marks `bbox.x >= vpW` invisible). It is NOT suppressed
+    // (no opacity:0 / visibility:hidden) and stays IN FLOW, so it still sets its flex track's
+    // cross-size. Without a band the base's canonical desktop width freezes across every viewport and
+    // inflates the mobile track. The band must carry THIS width's measured geometry.
+    const slide = nodeAt("n2", "div", {
+      375: { cs: { display: "block", position: "static", opacity: "1", width: "220px" }, bbox: { x: 400, y: 0, width: 220, height: 432 }, visible: false },
+      1280: { cs: { display: "block", position: "static", opacity: "1", width: "285px" }, bbox: { x: 1500, y: 0, width: 285, height: 532 }, visible: false },
+      1920: { cs: { display: "block", position: "static", opacity: "1", width: "285px" }, bbox: { x: 2200, y: 0, width: 285, height: 532 }, visible: false },
+    });
+    const track = nodeAt("n1", "div", {
+      375: { cs: { display: "flex", position: "relative" }, bbox: { x: 0, y: 0, width: 375, height: 432 } },
+      1280: { cs: { display: "flex", position: "relative" }, bbox: { x: 0, y: 0, width: 1280, height: 532 } },
+      1920: { cs: { display: "flex", position: "relative" }, bbox: { x: 0, y: 0, width: 1920, height: 532 } },
+    }, [slide]);
+    const root = nodeAt("n0", "body", {}, [track]);
+    const css = generateCss(ir3(root), new Map());
+    assert.ok(baseRule(css, "n2").includes("width:285px"), `base bakes canonical width, got: ${baseRule(css, "n2")}`);
+    const mobile = bandRule(css, /max-width/, "n2");
+    assert.ok(mobile.includes("width:220px"), `mobile band must carry the measured 220px width, got: ${mobile}`);
+    assert.ok(!mobile.includes("display:none"), "an occupying off-viewport slide must stay in layout");
+  });
 });
 
 // Fix 1 — mobile nav chip-strip overlap. A horizontally-scrollable flex strip (overflow-x:auto
@@ -290,3 +352,1096 @@ describe("generateCss scroll-timeline animation suppression", () => {
     assert.ok(rule.includes("animation-name:fadeInUp"), `time-based reveal keeps its animation, got: ${rule}`);
   });
 });
+
+// ---------------------------------------------------------------------------
+// Per-viewport node builder (independent bbox / computed / sizing per width) plus a matching
+// 3-viewport IR wrapper — the fluid/centring/wrap detectors need ≥2 varying widths to run.
+const XVPS = [375, 768, 1280];
+type XPerVp = { cs?: StyleMap; bbox: BBox; sizing?: RawSizing; visible?: boolean };
+function xNode(id: string, tag: string, byVp: Record<number, XPerVp>, children: IRChild[] = []): IRNode {
+  const computedByVp: Record<number, StyleMap> = {};
+  const bboxByVp: Record<number, BBox> = {};
+  const visibleByVp: Record<number, boolean> = {};
+  const sizingByVp: Record<number, RawSizing> = {};
+  for (const vp of XVPS) {
+    const s = byVp[vp]!;
+    computedByVp[vp] = computed(s.cs);
+    bboxByVp[vp] = s.bbox;
+    visibleByVp[vp] = s.visible ?? true;
+    if (s.sizing) sizingByVp[vp] = s.sizing;
+  }
+  const n: IRNode = { id, tag, attrs: {}, visibleByVp, bboxByVp, computedByVp, children };
+  if (Object.keys(sizingByVp).length) n.sizingByVp = sizingByVp;
+  return n;
+}
+function xIr(root: IRNode): IR {
+  const ir = irWith(root);
+  ir.doc.viewports = XVPS;
+  ir.doc.sampleViewports = XVPS;
+  ir.doc.perViewport = Object.fromEntries(XVPS.map((vp) => [vp, { scrollHeight: 800, scrollWidth: vp, htmlBg: "rgb(255, 255, 255)", bodyBg: "rgb(255, 255, 255)", bodyColor: "rgb(0, 0, 0)", bodyFont: "Arial" }]));
+  return ir;
+}
+/** Every `.c<id>{…}` body (base + banded) concatenated, for asserting a value appears at some vp. */
+function allRulesX(css: string, id: string): string {
+  const re = new RegExp(`\\.c${id}\\{([^}]*)\\}`, "g");
+  let out = "", m: RegExpExecArray | null;
+  while ((m = re.exec(css))) out += m[1] + ";";
+  return out;
+}
+/** The `.c<id>{…}` body inside the first @media block whose query matches `mediaRe`. */
+function xBandRule(css: string, mediaRe: RegExp, id: string): string {
+  for (const m of css.matchAll(/@media ([^{]+) \{\n([\s\S]*?)\n\}/g)) {
+    if (!mediaRe.test(m[1]!)) continue;
+    const r = m[2]!.match(new RegExp(`\\.c${id}\\{([^}]*)\\}`));
+    if (r) return r[1]!;
+  }
+  return "";
+}
+
+// BUG A — a padded pill/section with LITERAL equal side margins (a fraction of the viewport, varying
+// across widths) must keep those px margins per band. The width-fill sizing probe is what tells the
+// centring detector these are load-bearing spacing, not margin-auto centring slack: on a box the
+// probe reads as a container-fill (width:100% reproduces it), `margin:auto` resolves to 0 and would
+// blow the box out to full-bleed, deleting the real margins.
+describe("generateCss literal-margin vs auto-centring", () => {
+  const fill = (): RawSizing => ({ wAuto: false, wFill: true, hAuto: true, hFill: true });
+  // A flex parent spanning the whole viewport, holding one padded pill child that fills the space
+  // BETWEEN its literal side margins (box + 2×margin == container at every width).
+  function pill() {
+    const child = xNode("n1", "div", {
+      375: { cs: { display: "flex", marginLeft: "15px", marginRight: "15px", width: "345px" }, bbox: { x: 15, y: 0, width: 345, height: 62 }, sizing: fill() },
+      768: { cs: { display: "flex", marginLeft: "30.7188px", marginRight: "30.7188px", width: "706.562px" }, bbox: { x: 30.72, y: 0, width: 706.56, height: 62 }, sizing: fill() },
+      1280: { cs: { display: "flex", marginLeft: "25.5938px", marginRight: "25.5938px", width: "1228.81px" }, bbox: { x: 25.59, y: 0, width: 1228.81, height: 62 }, sizing: fill() },
+    });
+    const parent = xNode("n0", "body", {
+      375: { cs: { display: "flex" }, bbox: { x: 0, y: 0, width: 375, height: 62 } },
+      768: { cs: { display: "flex" }, bbox: { x: 0, y: 0, width: 768, height: 62 } },
+      1280: { cs: { display: "flex" }, bbox: { x: 0, y: 0, width: 1280, height: 62 } },
+    }, [child]);
+    return parent;
+  }
+
+  it("keeps the literal px side margins on a width-filling pill (no mx-auto)", () => {
+    const css = generateCss(xIr(pill()), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/margin-left:auto/.test(all), `filling pill must not be centred with auto margins, got: ${all}`);
+    assert.ok(baseRule(css, "n1").includes("margin-left:25.5938px"), `base keeps the 1280 literal margin, got: ${baseRule(css, "n1")}`);
+    // The narrowest band (a `max-width` query with no `min-width`) carries the 375-vp literal margin.
+    const mobile = xBandRule(css, /^\(max-width/, "n1");
+    assert.ok(/margin-left:15px/.test(mobile), `mobile band keeps its literal 15px margin, got: ${mobile}`);
+  });
+
+  it("still emits margin:auto for a genuinely centred, width-CONSTRAINED block", () => {
+    // Content-sized (not a fill): the probe says width:auto re-derives it, width narrower than the
+    // container with symmetric slack that varies with width — real margin-auto centring.
+    const auto = (): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false });
+    const child = xNode("n1", "div", {
+      375: { cs: { display: "block", marginLeft: "15px", marginRight: "15px", width: "345px" }, bbox: { x: 15, y: 0, width: 345, height: 40 }, sizing: auto() },
+      768: { cs: { display: "block", marginLeft: "84px", marginRight: "84px", width: "600px" }, bbox: { x: 84, y: 0, width: 600, height: 40 }, sizing: auto() },
+      1280: { cs: { display: "block", marginLeft: "340px", marginRight: "340px", width: "600px" }, bbox: { x: 340, y: 0, width: 600, height: 40 }, sizing: auto() },
+    });
+    const parent = xNode("n0", "body", {
+      375: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 375, height: 40 } },
+      768: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 768, height: 40 } },
+      1280: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 1280, height: 40 } },
+    }, [child]);
+    const css = generateCss(xIr(parent), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(/margin-left:auto/.test(all), `a constrained centred block should still auto-centre, got: ${all}`);
+  });
+
+  // A centred `max-width` container whose cap is FLUID — `max-width: min(1272px, 100vw − 2·gutter)`
+  // resolves to a DIFFERENT px at every width (311/673/1145). The block is centred at every sample
+  // (symmetric positive gaps that scale with width). It must auto-centre (`mx-auto`) with per-band
+  // caps, NOT freeze to literal per-band `margin-left` (which pins it left at non-captured widths).
+  it("auto-centres a container with a per-viewport (fluid) max-width cap", () => {
+    // border-box block, max-width per vp, box width == cap, symmetric gaps everywhere.
+    const child = xNode("n1", "div", {
+      375: { cs: { display: "block", boxSizing: "border-box", maxWidth: "311px", marginLeft: "0px", marginRight: "0px", width: "311px" }, bbox: { x: 32, y: 0, width: 311, height: 200 } },
+      768: { cs: { display: "block", boxSizing: "border-box", maxWidth: "673.2px", marginLeft: "0px", marginRight: "0px", width: "673.2px" }, bbox: { x: 47.4, y: 0, width: 673.2, height: 200 } },
+      1280: { cs: { display: "block", boxSizing: "border-box", maxWidth: "1145.08px", marginLeft: "0px", marginRight: "0px", width: "1145.08px" }, bbox: { x: 67.46, y: 0, width: 1145.08, height: 200 } },
+    });
+    const parent = xNode("n0", "body", {
+      375: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 375, height: 200 } },
+      768: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 768, height: 200 } },
+      1280: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 1280, height: 200 } },
+    }, [child]);
+    const css = generateCss(xIr(parent), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(/margin-left:auto/.test(all), `fluid-cap centred container must auto-centre, got: ${all}`);
+    assert.ok(!/margin-left:0?67|margin-left:32px|margin-left:47/.test(all), `must NOT bake literal per-band left margins, got: ${all}`);
+    // The per-viewport caps survive as banded max-width (the canonical 1145.08 at base, others banded).
+    assert.ok(baseRule(css, "n1").includes("max-width:1145.08px"), `base carries the canonical cap, got: ${baseRule(css, "n1")}`);
+    const mobile = xBandRule(css, /^\(max-width/, "n1");
+    assert.ok(/max-width:311px/.test(mobile), `mobile band carries its own fluid cap, got: ${mobile}`);
+  });
+
+  // Same centred `width:100%; max-width:min(Wpx, …); margin:0 auto` container, but it is a FLEX ITEM
+  // (its parent is display:flex). planWidth case (a) and centeredAtVp both bail on flex/grid items, so
+  // without isCappedCenteredContainer it would freeze its captured per-band side margins (32/47/67px)
+  // and left-align at every non-captured width. margin:auto centres a flex item correctly, and the
+  // retained per-band max-width cap keeps it safe (auto only absorbs the centring slack).
+  it("auto-centres a fluid-max-width container that is a FLEX ITEM (parent is flex)", () => {
+    const child = xNode("n1", "div", {
+      375: { cs: { display: "block", boxSizing: "border-box", maxWidth: "311px", marginLeft: "32px", marginRight: "32px", width: "311px" }, bbox: { x: 32, y: 0, width: 311, height: 200 } },
+      768: { cs: { display: "block", boxSizing: "border-box", maxWidth: "673.2px", marginLeft: "47.4px", marginRight: "47.4px", width: "673.2px" }, bbox: { x: 47.4, y: 0, width: 673.2, height: 200 } },
+      1280: { cs: { display: "block", boxSizing: "border-box", maxWidth: "1145.08px", marginLeft: "67.46px", marginRight: "67.46px", width: "1145.08px" }, bbox: { x: 67.46, y: 0, width: 1145.08, height: 200 } },
+    });
+    const parent = xNode("n0", "body", {
+      375: { cs: { display: "flex", flexDirection: "column" }, bbox: { x: 0, y: 0, width: 375, height: 200 } },
+      768: { cs: { display: "flex", flexDirection: "column" }, bbox: { x: 0, y: 0, width: 768, height: 200 } },
+      1280: { cs: { display: "flex", flexDirection: "column" }, bbox: { x: 0, y: 0, width: 1280, height: 200 } },
+    }, [child]);
+    const css = generateCss(xIr(parent), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(/margin-left:auto/.test(all), `flex-item fluid-cap centred container must auto-centre, got: ${all}`);
+    assert.ok(!/margin-left:32px|margin-left:47|margin-left:0?67/.test(all), `must NOT bake literal per-band left margins, got: ${all}`);
+    assert.ok(baseRule(css, "n1").includes("max-width:1145.08px"), `base carries the canonical cap, got: ${baseRule(css, "n1")}`);
+  });
+});
+
+// BUG C — a single-line text leaf whose unwrapped width nearly fills its column at every width gets
+// `white-space:nowrap`, so a sub-pixel column shortfall in the clone can't wrap it to a second line.
+describe("generateCss wrap-vulnerable single-line text", () => {
+  // Text bbox exactly fills the column (wMax == avail == bbox.width) at every width, single line
+  // (height == line-height), and is genuinely wrappable (wMin < wMax).
+  function edgeText(wMin: number) {
+    const szAt = (w: number): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false, wMin, wMax: w });
+    const leaf = xNode("n1", "div", {
+      375: { cs: { display: "block", lineHeight: "24px" }, bbox: { x: 0, y: 0, width: 107.81, height: 24 }, sizing: szAt(107.81) },
+      768: { cs: { display: "block", lineHeight: "24px" }, bbox: { x: 0, y: 0, width: 107.81, height: 24 }, sizing: szAt(107.81) },
+      1280: { cs: { display: "block", lineHeight: "20px" }, bbox: { x: 0, y: 0, width: 107.81, height: 20 }, sizing: szAt(107.81) },
+    }, [{ text: "CEO — Academy" }]);
+    const parent = xNode("n0", "body", {
+      375: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 107.81, height: 24 } },
+      768: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 107.81, height: 24 } },
+      1280: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 107.81, height: 20 } },
+    }, [leaf]);
+    return parent;
+  }
+
+  it("emits white-space:nowrap for text flush against its column edge", () => {
+    const css = generateCss(xIr(edgeText(58.33)), new Map());
+    assert.ok(baseRule(css, "n1").includes("white-space:nowrap"), `edge-flush single-line text should get nowrap, got: ${baseRule(css, "n1")}`);
+  });
+
+  it("does NOT emit nowrap for a single unbreakable token (wMin == wMax — can't wrap)", () => {
+    const css = generateCss(xIr(edgeText(107.81)), new Map());
+    assert.ok(!baseRule(css, "n1").includes("white-space:nowrap"), `an unbreakable token needs no nowrap, got: ${baseRule(css, "n1")}`);
+  });
+
+  it("does NOT emit nowrap for a genuinely wrapping multi-line paragraph", () => {
+    // Two line boxes tall (height ≈ 2×line-height) → already wrapping, must stay wrappable.
+    const wMin = 100, wMax = 400;
+    const szAt = (): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false, wMin, wMax });
+    const para = xNode("n1", "p", {
+      375: { cs: { display: "block", lineHeight: "24px" }, bbox: { x: 0, y: 0, width: 345, height: 72 }, sizing: szAt() },
+      768: { cs: { display: "block", lineHeight: "24px" }, bbox: { x: 0, y: 0, width: 700, height: 48 }, sizing: szAt() },
+      1280: { cs: { display: "block", lineHeight: "24px" }, bbox: { x: 0, y: 0, width: 400, height: 48 }, sizing: szAt() },
+    }, [{ text: "A longer paragraph that wraps across multiple lines depending on the width." }]);
+    const parent = xNode("n0", "body", {
+      375: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 345, height: 72 } },
+      768: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 700, height: 48 } },
+      1280: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 400, height: 48 } },
+    }, [para]);
+    const css = generateCss(xIr(parent), new Map());
+    assert.ok(!allRulesX(css, "n1").includes("white-space:nowrap"), `a wrapping paragraph must not be forced nowrap, got: ${allRulesX(css, "n1")}`);
+  });
+
+  it("does NOT emit nowrap for text with comfortable slack in its container", () => {
+    const szAt = (): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false, wMin: 60, wMax: 90 });
+    const leaf = xNode("n1", "div", {
+      375: { cs: { display: "block", lineHeight: "20px" }, bbox: { x: 0, y: 0, width: 90, height: 20 }, sizing: szAt() },
+      768: { cs: { display: "block", lineHeight: "20px" }, bbox: { x: 0, y: 0, width: 90, height: 20 }, sizing: szAt() },
+      1280: { cs: { display: "block", lineHeight: "20px" }, bbox: { x: 0, y: 0, width: 90, height: 20 }, sizing: szAt() },
+    }, [{ text: "Nav link" }]);
+    // Wide container (300px+) — the 90px text has plenty of room, no wrap risk.
+    const parent = xNode("n0", "body", {
+      375: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 375, height: 20 } },
+      768: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 768, height: 20 } },
+      1280: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 1280, height: 20 } },
+    }, [leaf]);
+    const css = generateCss(xIr(parent), new Map());
+    assert.ok(!baseRule(css, "n1").includes("white-space:nowrap"), `slack text needs no nowrap, got: ${baseRule(css, "n1")}`);
+  });
+});
+
+// Cross-band transform identity — a node with a NON-identity transform at one band must emit the
+// explicit identity `transform:none` at the bands where the source is untransformed, so the
+// transform can't cascade across bands and freeze at a width the source left untransformed.
+describe("generateCss cross-band transform identity", () => {
+  it("emits transform:none at a band where a node with a non-identity transform elsewhere is identity", () => {
+    const el = xNode("n1", "div", {
+      375: { cs: { transform: "none" }, bbox: { x: 0, y: 0, width: 375, height: 40 } },
+      768: { cs: { transform: "matrix(1, 0, 0, 1, 40, 0)" }, bbox: { x: 40, y: 0, width: 375, height: 40 } },
+      1280: { cs: { transform: "matrix(1, 0, 0, 1, 40, 0)" }, bbox: { x: 40, y: 0, width: 375, height: 40 } },
+    });
+    const root = xNode("n0", "body", { 375: { bbox: { x: 0, y: 0, width: 375, height: 40 } }, 768: { bbox: { x: 0, y: 0, width: 768, height: 40 } }, 1280: { bbox: { x: 0, y: 0, width: 1280, height: 40 } } }, [el]);
+    const css = generateCss(xIr(root), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(/transform:matrix/.test(all), `the non-identity transform must be emitted, got: ${all}`);
+    assert.ok(/transform:none/.test(all), `the identity band must emit transform:none so it can't cascade, got: ${all}`);
+  });
+
+  it("does NOT emit transform:none for a node that is identity at every band", () => {
+    const el = xNode("n1", "div", {
+      375: { cs: { transform: "none" }, bbox: { x: 0, y: 0, width: 375, height: 40 } },
+      768: { cs: { transform: "none" }, bbox: { x: 0, y: 0, width: 375, height: 40 } },
+      1280: { cs: { transform: "none" }, bbox: { x: 0, y: 0, width: 375, height: 40 } },
+    });
+    const root = xNode("n0", "body", { 375: { bbox: { x: 0, y: 0, width: 375, height: 40 } }, 768: { bbox: { x: 0, y: 0, width: 768, height: 40 } }, 1280: { bbox: { x: 0, y: 0, width: 1280, height: 40 } } }, [el]);
+    const css = generateCss(xIr(root), new Map());
+    assert.ok(!allRulesX(css, "n1").includes("transform:none"), `an always-identity node needs no explicit transform, got: ${allRulesX(css, "n1")}`);
+  });
+});
+
+// BUG 1 — heightFlows must consult the sizing probe. A circular parent/child pair of authored-height
+// boxes (two nested viewport-height containers whose only children are absolutely positioned) used to
+// "explain each other away": the outer read content-driven (its content IS the inner box) and the
+// inner read stretched (it equals the outer's content height) — both dropped, collapsing a hero to
+// 0px. The probe now proves each height authored-explicit (hAuto:false, hFill:false); heightFlows
+// bails so both survive.
+describe("generateCss circular authored-height (probe bail)", () => {
+  const authored = (): RawSizing => ({ wAuto: false, wFill: false, hAuto: false, hFill: false });
+  function hero(hByVp: Record<number, number>) {
+    // an absolutely-positioned decoration inside the inner box (contributes no in-flow content height)
+    const abs = xNode("n3", "div", {
+      375: { cs: { position: "absolute" }, bbox: { x: 0, y: 0, width: 375, height: hByVp[375]! } },
+      768: { cs: { position: "absolute" }, bbox: { x: 0, y: 0, width: 768, height: hByVp[768]! } },
+      1280: { cs: { position: "absolute" }, bbox: { x: 0, y: 0, width: 1280, height: hByVp[1280]! } },
+    });
+    const inner = xNode("n2", "div", {
+      375: { cs: { display: "flex", height: `${hByVp[375]}px` }, bbox: { x: 0, y: 0, width: 375, height: hByVp[375]! }, sizing: authored() },
+      768: { cs: { display: "flex", height: `${hByVp[768]}px` }, bbox: { x: 0, y: 0, width: 768, height: hByVp[768]! }, sizing: authored() },
+      1280: { cs: { display: "flex", height: `${hByVp[1280]}px` }, bbox: { x: 0, y: 0, width: 1280, height: hByVp[1280]! }, sizing: authored() },
+    }, [abs]);
+    const outer = xNode("n1", "div", {
+      375: { cs: { display: "flex", height: `${hByVp[375]}px` }, bbox: { x: 0, y: 0, width: 375, height: hByVp[375]! }, sizing: authored() },
+      768: { cs: { display: "flex", height: `${hByVp[768]}px` }, bbox: { x: 0, y: 0, width: 768, height: hByVp[768]! }, sizing: authored() },
+      1280: { cs: { display: "flex", height: `${hByVp[1280]}px` }, bbox: { x: 0, y: 0, width: 1280, height: hByVp[1280]! }, sizing: authored() },
+    }, [inner]);
+    return xNode("n0", "body", {
+      375: { bbox: { x: 0, y: 0, width: 375, height: hByVp[375]! } },
+      768: { bbox: { x: 0, y: 0, width: 768, height: hByVp[768]! } },
+      1280: { bbox: { x: 0, y: 0, width: 1280, height: hByVp[1280]! } },
+    }, [outer]);
+  }
+
+  it("keeps both heights when the probe proves them authored-explicit", () => {
+    const css = generateCss(xIr(hero({ 375: 771, 768: 900, 1280: 800 })), new Map());
+    const outer = allRulesX(css, "n1");
+    const inner = allRulesX(css, "n2");
+    assert.ok(/height:800px/.test(outer), `outer must keep its canonical authored height, got: ${outer}`);
+    assert.ok(/height:800px/.test(inner), `inner must keep its canonical authored height, got: ${inner}`);
+  });
+
+  it("still flows a genuinely content-sized varying height (probe hAuto:true)", () => {
+    // Same shape but the probe says auto reproduces the box — the varying height is real content, safe
+    // to drop. Give it an in-flow text child so it reads content-driven.
+    const auto = (): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false });
+    const mk = (h: number, w: number): XPerVp => ({ cs: { display: "block", height: `${h}px` }, bbox: { x: 0, y: 0, width: w, height: h }, sizing: auto() });
+    const inner = xNode("n2", "div", { 375: mk(200, 375), 768: mk(260, 768), 1280: mk(320, 1280) }, [{ text: "flowing content" } as IRChild]);
+    // pad the box so height == content is plausible per contentDriven's text branch
+    const root = xNode("n0", "body", { 375: { bbox: { x: 0, y: 0, width: 375, height: 200 } }, 768: { bbox: { x: 0, y: 0, width: 768, height: 260 } }, 1280: { bbox: { x: 0, y: 0, width: 1280, height: 320 } } }, [inner]);
+    const css = generateCss(xIr(root), new Map());
+    assert.ok(!/height:320px/.test(allRulesX(css, "n2")), `a probe-auto content height should still flow, got: ${allRulesX(css, "n2")}`);
+  });
+});
+
+// BUG 2 — a space-distributing flex column (justify-content: space-between/around/evenly, or a packed
+// center/flex-end) sets the free space its children spread through, so the last child reaching the box
+// bottom is NOT content evidence. heightFlows used to read that as content-driven and drop the box's
+// authored height, collapsing the distributed gaps.
+describe("generateCss space-distributing flex column keeps its height", () => {
+  // hAuto:true (auto reproduces the box at capture, because distribution places the last child at the
+  // bottom) — so the sizing probe does NOT forbid the drop. Wrappable text inside makes heightProbeDrops
+  // abstain, isolating heightFlows' space-distribution disqualification as the sole arbiter.
+  const auto = (): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false });
+  const textChild = { text: "a line of distributed content" } as IRChild;
+  function distributed(justify: string) {
+    // two content-sized blocks; the last sits at the box bottom because the column distributes space
+    const top = xNode("n2", "div", {
+      375: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 375, height: 40 } },
+      768: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 768, height: 40 } },
+      1280: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 1280, height: 40 } },
+    }, [textChild]);
+    const bottomH = (h: number): XPerVp => ({ cs: { display: "block" }, bbox: { x: 0, y: h - 40, width: 375, height: 40 } });
+    const bot = xNode("n3", "div", { 375: bottomH(360), 768: bottomH(500), 1280: bottomH(600) }, [textChild]);
+    const col = xNode("n1", "div", {
+      375: { cs: { display: "flex", flexDirection: "column", justifyContent: justify, height: "360px" }, bbox: { x: 0, y: 0, width: 375, height: 360 }, sizing: auto() },
+      768: { cs: { display: "flex", flexDirection: "column", justifyContent: justify, height: "500px" }, bbox: { x: 0, y: 0, width: 768, height: 500 }, sizing: auto() },
+      1280: { cs: { display: "flex", flexDirection: "column", justifyContent: justify, height: "600px" }, bbox: { x: 0, y: 0, width: 1280, height: 600 }, sizing: auto() },
+    }, [top, bot]);
+    return xNode("n0", "body", { 375: { bbox: { x: 0, y: 0, width: 375, height: 360 } }, 768: { bbox: { x: 0, y: 0, width: 768, height: 500 } }, 1280: { bbox: { x: 0, y: 0, width: 1280, height: 600 } } }, [col]);
+  }
+
+  for (const j of ["space-between", "space-around", "space-evenly"]) {
+    it(`keeps the authored height under justify-content:${j}`, () => {
+      const css = generateCss(xIr(distributed(j)), new Map());
+      assert.ok(/height:600px/.test(allRulesX(css, "n1")), `${j} column must keep its distributing height, got: ${allRulesX(css, "n1")}`);
+    });
+  }
+
+  it("still flows a flex-start column whose height truly equals its content", () => {
+    // justify-content:flex-start (default) — the last child at the bottom IS content-driven, so the
+    // varying height flows (drops) as before.
+    const css = generateCss(xIr(distributed("flex-start")), new Map());
+    assert.ok(!/height:600px/.test(allRulesX(css, "n1")), `a packed-top column should still flow, got: ${allRulesX(css, "n1")}`);
+  });
+});
+
+// BUG 3 — a lottie mount pins its captured per-viewport height so the runtime player's aspect-sized
+// svg fills a definite box instead of inflating past its neighbours. Threaded via collectNodeRules'
+// lottieMounts set (populated from the lottie spec item cids).
+describe("collectNodeRules lottie mount height pin", () => {
+  const auto = (): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false });
+  function mountFixture() {
+    // the mount is a flex box; its only child is a content-sized placeholder svg — without the pin the
+    // box height flows/collapses and the runtime svg inflates by aspect.
+    const svg = xNode("n2", "svg", {
+      375: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 375, height: 94 } },
+      768: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 768, height: 195 } },
+      1280: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 1280, height: 227 } },
+    });
+    const mount = xNode("n1", "div", {
+      375: { cs: { display: "flex", height: "94px" }, bbox: { x: 0, y: 0, width: 375, height: 94 }, sizing: auto() },
+      768: { cs: { display: "flex", height: "195px" }, bbox: { x: 0, y: 0, width: 768, height: 195 }, sizing: auto() },
+      1280: { cs: { display: "flex", height: "227px" }, bbox: { x: 0, y: 0, width: 1280, height: 227 }, sizing: auto() },
+    }, [svg]);
+    return xNode("n0", "body", { 375: { bbox: { x: 0, y: 0, width: 375, height: 94 } }, 768: { bbox: { x: 0, y: 0, width: 768, height: 195 } }, 1280: { bbox: { x: 0, y: 0, width: 1280, height: 227 } } }, [mount]);
+  }
+
+  it("pins the captured height on a mount node", () => {
+    const rules = collectNodeRules(xIr(mountFixture()), new Map(), undefined, undefined, undefined, false, new Set(["n1"]));
+    const nr = rules.get("n1");
+    assert.ok(nr, "mount rule must exist");
+    const all = [nr!.base.get("height"), ...nr!.bands.map((b) => b.decls.get("height"))].filter(Boolean).join(";");
+    assert.ok(/227px/.test(all), `canonical mount height must be pinned, got: ${all}`);
+    assert.ok(/94px/.test(all), `narrow-band mount height must be pinned, got: ${all}`);
+  });
+
+  it("leaves a non-mount box unpinned (flows its varying content height)", () => {
+    const rules = collectNodeRules(xIr(mountFixture()), new Map(), undefined, undefined, undefined, false, new Set());
+    const nr = rules.get("n1")!;
+    const all = [nr.base.get("height"), ...nr.bands.map((b) => b.decls.get("height"))].filter(Boolean).join(";");
+    assert.ok(!/227px/.test(all), `without the mount flag the varying height should flow, got: ${all}`);
+  });
+});
+
+// The reset ships a rule that forces the lottie runtime svg/canvas to fit its overlay box. The
+// player re-mounts its media into an absolute overlay that fills the host's pinned (per-viewport)
+// height; without this rule an aspect-mismatched viewBox (a portrait animation in a shorter,
+// letterboxed source box) inflates past that height. Scoped to the runtime-marked host only, so it
+// is inert when a page has no lottie.
+describe("RESET_CSS lottie runtime-fit rule", () => {
+  it("constrains the runtime svg/canvas to the overlay box, scoped to the marked host", () => {
+    assert.match(RESET_CSS, /\[data-ditto-lottie\]\s*>\s*div\s*>\s*svg/);
+    assert.match(RESET_CSS, /\[data-ditto-lottie\]\s*>\s*div\s*>\s*canvas/);
+    // the rule must pin both dimensions so height:100% resolves against the definite overlay
+    const m = RESET_CSS.match(/\[data-ditto-lottie\][^{]*\{([^}]*)\}/);
+    assert.ok(m, "the data-ditto-lottie rule must be present");
+    assert.match(m![1], /width:\s*100%/);
+    assert.match(m![1], /height:\s*100%/);
+  });
+
+  it("does not affect the pre-swap placeholder (a direct-child svg, not nested under a div)", () => {
+    // The selector targets `> div > svg` (the runtime overlay), never a `> svg` placeholder, so the
+    // captured placeholder keeps its own pinned classes and pre/post-swap geometry stays identical.
+    assert.ok(
+      !/\[data-ditto-lottie\]\s*>\s*svg\b/.test(RESET_CSS),
+      "the rule must not target a direct-child placeholder svg",
+    );
+  });
+});
+
+// Defect E — a content-sized flex ROW's items are dropped to `width:auto` only when NO shrink fired
+// (positive slack ⇒ items at content size). But a WRAPPING text leaf paints at its balanced-wrap
+// width, which is BELOW its max-content: `width:auto` on the block child fills the line to
+// max-content and left-aligns it, so the narrow right-pushed paragraph blows out to full-width. The
+// sizing probe already read `wAuto:false` (auto does NOT reproduce the width); it must veto the
+// whole line (the rule is all-or-nothing — dropping a subset shifts siblings via justify-content).
+describe("generateCss content-sized flex row (probe veto for wrapping text)", () => {
+  // One <p> child, sole item of a `flex; justify-content:flex-end` row, `flex:0 1 auto`, that paints
+  // narrower than the container at every width (wraps below max-content) with positive slack.
+  function missionRow(pSizing: RawSizing) {
+    const p = xNode("n1", "p", {
+      375: { cs: { display: "block", flexGrow: "0", flexShrink: "1", flexBasis: "auto", width: "276px" }, bbox: { x: 69, y: 0, width: 276, height: 80 }, sizing: pSizing },
+      768: { cs: { display: "block", flexGrow: "0", flexShrink: "1", flexBasis: "auto", width: "529.922px" }, bbox: { x: 176, y: 0, width: 529.92, height: 60 }, sizing: pSizing },
+      1280: { cs: { display: "block", flexGrow: "0", flexShrink: "1", flexBasis: "auto", width: "774.141px" }, bbox: { x: 455, y: 0, width: 774.14, height: 40 }, sizing: pSizing },
+    }, [{ text: "Our UX staffing and recruiting teams place the best talent from around the world." }]);
+    return xNode("n0", "body", {
+      375: { cs: { display: "flex", flexDirection: "row", justifyContent: "flex-end" }, bbox: { x: 0, y: 0, width: 375, height: 80 } },
+      768: { cs: { display: "flex", flexDirection: "row", justifyContent: "flex-end" }, bbox: { x: 0, y: 0, width: 706.56, height: 60 } },
+      1280: { cs: { display: "flex", flexDirection: "row", justifyContent: "flex-end" }, bbox: { x: 0, y: 0, width: 1228.81, height: 40 } },
+    }, [p]);
+  }
+
+  it("keeps a width on a wrapping paragraph the probe proved is not auto-reproducible", () => {
+    // Probe ground truth: width:auto does NOT reproduce (wAuto:false) — the painted width is the
+    // balanced-wrap width, below max-content (wMax).
+    const notAuto = (): RawSizing => ({ wAuto: false, wFill: false, hAuto: true, hFill: false, wMin: 95.88, wMax: 706.56 });
+    const css = generateCss(xIr(missionRow(notAuto())), new Map());
+    const all = allRulesX(css, "n1");
+    // It must NOT be emitted as content-auto (which drops width entirely and fills the line). The
+    // width plan falls to a real width — a fluid percentage or baked px — so the narrow column survives.
+    assert.ok(/width:/.test(all), `wrapping paragraph must keep a width, not collapse to auto, got: ${all}`);
+    assert.ok(!/width:auto/.test(all), `probe said wAuto:false — must not emit width:auto, got: ${all}`);
+  });
+
+  it("still drops width:auto on a genuinely content-sized row item the probe confirms", () => {
+    // Probe agrees width:auto reproduces (wAuto:true) — a toolbar/menu item whose width is its
+    // content. The content-sized-flex-row law should still fire and emit auto (no baked px band).
+    const isAuto = (): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false, wMin: 95.88, wMax: 706.56 });
+    const css = generateCss(xIr(missionRow(isAuto())), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/width:\d/.test(all), `content-sized item must drop its baked px width, got: ${all}`);
+  });
+});
+
+describe("generateCss fluid percent snap-up for content-fit nowrap pill (task #26)", () => {
+  // A nowrap flex pill, sole child of a flex COLUMN, that paints at its own max-content width
+  // (bbox.width == wMax) at every viewport — a load-bearing % width that, rounded to the nearest
+  // 0.5%, lands BELOW the intrinsic content and wraps to a second line. Real evidence: a footer
+  // pill 245.94px in a 343px column at 375 (71.70% → 71.5% → 245.24px < 245.94 → wrap).
+  // Numbers below are the captured run's (375 / 768 / 1280).
+  // Per-vp pill widths mirror the real run: at 768 the column is narrower than the pill's content, so
+  // the pill shrinks to fill it (221.33 == container); at 375/1280 it sits at its max-content (245.94).
+  // A CONSTANT max-content across vps keeps contentSizedColumnItem from firing (its widths don't vary),
+  // so the width falls through to the fluid-percent (percentVp) path — exactly the real code path.
+  const wMax = 245.94;
+  function pillIn(colWidths: [number, number, number], wMinOrWMax: { wMin: number; wMax: number }) {
+    const pillW: Record<number, number> = { 375: 245.94, 768: 221.33, 1280: 245.94 };
+    const sz = (): RawSizing => ({ wAuto: false, wFill: false, hAuto: true, hFill: true, ...wMinOrWMax });
+    const pill = xNode("n1", "a", {
+      375: { cs: { display: "flex", whiteSpace: "nowrap" }, bbox: { x: 0, y: 0, width: pillW[375]!, height: 40 }, sizing: sz() },
+      768: { cs: { display: "flex", whiteSpace: "nowrap" }, bbox: { x: 0, y: 0, width: pillW[768]!, height: 40 }, sizing: sz() },
+      1280: { cs: { display: "flex", whiteSpace: "nowrap" }, bbox: { x: 0, y: 0, width: pillW[1280]!, height: 40 }, sizing: sz() },
+    }, [{ text: "Certified B Corporation" }]);
+    return xNode("n0", "body", {
+      375: { cs: { display: "flex", flexDirection: "column" }, bbox: { x: 0, y: 0, width: colWidths[0], height: 40 } },
+      768: { cs: { display: "flex", flexDirection: "column" }, bbox: { x: 0, y: 0, width: colWidths[1], height: 40 } },
+      1280: { cs: { display: "flex", flexDirection: "column" }, bbox: { x: 0, y: 0, width: colWidths[2], height: 40 } },
+    }, [pill]);
+  }
+
+  /** Collect every emitted `width:N%` for `id` across the base rule and all @media bands. */
+  function emittedPercents(css: string, id: string) {
+    const bodies: string[] = [];
+    // base rule
+    const base = css.match(new RegExp(`\\.c${id}\\{([^}]*)\\}`));
+    if (base) bodies.push(base[1]!);
+    // banded rules
+    for (const m of css.matchAll(/@media ([^{]+) \{\n([\s\S]*?)\n\}/g)) {
+      const r = m[2]!.match(new RegExp(`\\.c${id}\\{([^}]*)\\}`));
+      if (r) bodies.push(r[1]!);
+    }
+    const pcts: number[] = [];
+    for (const b of bodies) {
+      const w = b.match(/width:([\d.]+)%/);
+      if (w) pcts.push(parseFloat(w[1]!));
+    }
+    return { pcts, bodies };
+  }
+
+  it("snaps the percent UP so the emitted width never lands below the pill's content (no wrap)", () => {
+    // 245.94 in 343 → 71.70% (nearest 71.5% = 245.24 < wMax); in 392 → 62.74% (nearest 62.5% = 245.0 < wMax).
+    const css = generateCss(xIr(pillIn([343, 221.33, 392], { wMin: 189.72, wMax })), new Map());
+    const { pcts } = emittedPercents(css, "n1");
+    assert.ok(pcts.length > 0, `pill should carry a fluid width:%, got none`);
+    // Every emitted % must clear the content width against the vp where it applies. The two content-
+    // fit viewports are 343 (71.70% band) and 392 (62.74% band); resolve each candidate % and require
+    // at least the 343-container % ≥ 245.94.
+    const at343 = pcts.filter((p) => Math.abs((p / 100) * 343 - 245.94) <= 3);
+    assert.ok(at343.some((p) => (p / 100) * 343 >= 245.94 - 0.01),
+      `375 pill % must resolve ≥ 245.94px in a 343px column, got pcts=${pcts.join(",")} → ${at343.map((p) => ((p / 100) * 343).toFixed(2)).join(",")}px`);
+    // Nearest-rounding would have emitted 71.5% (= 245.24). Assert the fix bumped it up to 72%.
+    assert.ok(pcts.includes(72) || pcts.some((p) => (p / 100) * 343 >= 245.94),
+      `expected snap-UP to 72% (246.96px), got ${pcts.join(",")}`);
+  });
+
+  it("keeps round-to-NEAREST for an ordinary box comfortably inside its container (no churn)", () => {
+    // Same geometry but NOT content-fit: bbox 245.94 sits well below wMax (400), so there is slack —
+    // wrapping can't happen, and the default nearest rounding (71.5%) must be preserved.
+    const rootPill = pillIn([343, 221.33, 392], { wMin: 100, wMax: 400 });
+    const css2 = generateCss(xIr(rootPill), new Map());
+    const { pcts } = emittedPercents(css2, "n1");
+    // 71.70% and 62.74% both round to nearest (71.5%, 63.0%... actually 62.74→62.5) — assert 71.5 present.
+    assert.ok(pcts.includes(71.5), `an ordinary box must keep nearest rounding (71.5%), got ${pcts.join(",")}`);
+    assert.ok(!pcts.includes(72), `an ordinary box must NOT be bumped up to 72%, got ${pcts.join(",")}`);
+  });
+});
+
+// Defect C (generate side) — a CSS marquee (infinite `@keyframes` animation) gated to a breakpoint
+// (Webflow's `max-lg` logo/text tracks) is `animation:none` at the base but runs at the narrow band.
+// The per-band transform delta at the animated width is a FROZEN mid-scroll phase; it must be
+// suppressed so the base holds and the runtime keyframes drive the transform (from translateX(0)).
+// (The upstream normalize pass zeroes the base residue — see neutralizeAnimatedTransforms; here the
+// base is already `none`, and this test covers the band-delta suppression.)
+describe("generateCss breakpoint-gated marquee transform band suppression (Defect C)", () => {
+  function logoStrip() {
+    const strip = xNode("n1", "div", {
+      375: { cs: { display: "grid", animationName: "track", animationIterationCount: "infinite", animationDuration: "35s", transform: "matrix(1, 0, 0, 1, -284.025, 0)" }, bbox: { x: 0, y: 0, width: 345, height: 100 } },
+      768: { cs: { display: "grid", animationName: "track", animationIterationCount: "infinite", animationDuration: "35s", transform: "matrix(1, 0, 0, 1, -280.982, 0)" }, bbox: { x: 0, y: 0, width: 706, height: 100 } },
+      1280: { cs: { display: "grid", animationName: "none", animationIterationCount: "1", transform: "none" }, bbox: { x: 0, y: 0, width: 1228, height: 145 } },
+    });
+    return xNode("n0", "body", { 375: { bbox: { x: 0, y: 0, width: 375, height: 100 } }, 768: { bbox: { x: 0, y: 0, width: 768, height: 100 } }, 1280: { bbox: { x: 0, y: 0, width: 1280, height: 145 } } }, [strip]);
+  }
+
+  it("does not bake the frozen mid-scroll translateX at the animated band", () => {
+    const css = generateCss(xIr(logoStrip()), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/matrix\(1, ?0, ?0, ?1, ?-\d/.test(all), `frozen marquee translateX must not be emitted at any band, got: ${all}`);
+  });
+
+  it("keeps a per-band transform of a NON-animated element", () => {
+    // A non-animated element whose transform genuinely varies per band keeps it (no animation owns it).
+    const el = xNode("n1", "div", {
+      375: { cs: { transform: "matrix(1, 0, 0, 1, -40, 0)" }, bbox: { x: -40, y: 0, width: 345, height: 100 } },
+      768: { cs: { transform: "none" }, bbox: { x: 0, y: 0, width: 706, height: 100 } },
+      1280: { cs: { transform: "none" }, bbox: { x: 0, y: 0, width: 1228, height: 100 } },
+    });
+    const root = xNode("n0", "body", { 375: { bbox: { x: 0, y: 0, width: 375, height: 100 } }, 768: { bbox: { x: 0, y: 0, width: 768, height: 100 } }, 1280: { bbox: { x: 0, y: 0, width: 1280, height: 100 } } }, [el]);
+    const css = generateCss(xIr(root), new Map());
+    assert.ok(/matrix\(1, ?0, ?0, ?1, ?-40/.test(allRulesX(css, "n1")), `a non-animated per-band offset must be kept, got: ${allRulesX(css, "n1")}`);
+  });
+});
+
+// text-wrap emission: a heading authored `text-wrap:balance` must survive to the clone, or the
+// title wraps differently. The initial `wrap` is elided (it's the default), so only authored
+// balance/pretty/nowrap ship.
+describe("generateCss text-wrap", () => {
+  it("emits an authored text-wrap:balance on a heading", () => {
+    const h1 = node("n1", "h1", computed({ textWrap: "balance" }));
+    const root = node("n0", "body", computed(), [h1]);
+    const css = generateCss(irWith(root), new Map());
+    assert.ok(/text-wrap:balance/.test(baseRule(css, "n1")), `text-wrap:balance emitted (got: ${baseRule(css, "n1")})`);
+  });
+
+  it("emits text-wrap:pretty", () => {
+    const p = node("n1", "p", computed({ textWrap: "pretty" }));
+    const root = node("n0", "body", computed(), [p]);
+    const css = generateCss(irWith(root), new Map());
+    assert.ok(/text-wrap:pretty/.test(baseRule(css, "n1")), `text-wrap:pretty emitted (got: ${baseRule(css, "n1")})`);
+  });
+
+  it("elides the default text-wrap:wrap (no noise)", () => {
+    const h1 = node("n1", "h1", computed({ textWrap: "wrap" }));
+    const root = node("n0", "body", computed(), [h1]);
+    const css = generateCss(irWith(root), new Map());
+    assert.ok(!/text-wrap/.test(baseRule(css, "n1")), `default text-wrap:wrap must not be emitted (got: ${baseRule(css, "n1")})`);
+  });
+
+  it("skips text-wrap on a child when it equals the parent (inherited)", () => {
+    // text-wrap is inherited: a child matching the parent's balance relies on inheritance.
+    const child = node("n2", "span", computed({ textWrap: "balance" }));
+    const h1 = node("n1", "h1", computed({ textWrap: "balance" }), [child]);
+    const root = node("n0", "body", computed(), [h1]);
+    const css = generateCss(irWith(root), new Map());
+    assert.ok(/text-wrap:balance/.test(baseRule(css, "n1")), "parent heading emits balance");
+    assert.ok(!/text-wrap/.test(baseRule(css, "n2")), `inherited child does not re-emit (got: ${baseRule(css, "n2")})`);
+  });
+});
+
+// FIX 4 — a library-sized carousel slide (a shrink-0 flex item with an injected inline `width:Npx`)
+// whose only in-flow child is a display:block box. A block box's `width:auto` IS its fill width, so
+// the sizing probe reports the child wAuto AND wFill both true. The circular-slide detector must count
+// that block-level fill child as width-DERIVING (it never establishes a width) and pin the slide's
+// captured px — otherwise the guard misreads the child as a genuine content-width source, bails, and
+// the slide content-sizes to a different width (ragged carousel rails).
+describe("generateCss circular carousel slide with a block-level fill child (FIX 4)", () => {
+  // The slide's child is display:block: its auto width equals the fill width, so BOTH probe bits fire.
+  const blockFill = (): RawSizing => ({ wAuto: true, wFill: true, hAuto: true, hFill: true });
+  function slideRow() {
+    // Uniform 220px slides at every viewport (Splide's inline width) inside a flex track.
+    const mkSlide = (id: string, childId: string): IRNode => {
+      const child = xNode(childId, "div", {
+        375: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 220, height: 357 }, sizing: blockFill() },
+        768: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 220, height: 357 }, sizing: blockFill() },
+        1280: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 220, height: 357 }, sizing: blockFill() },
+      }, [{ text: "Men's Tops & Shirts" } as IRChild]);
+      const slideCs = { display: "block", position: "static", flexShrink: "0", width: "220px" };
+      return xNode(id, "div", {
+        375: { cs: slideCs, bbox: { x: 0, y: 0, width: 220, height: 357 } },
+        768: { cs: slideCs, bbox: { x: 0, y: 0, width: 220, height: 357 } },
+        1280: { cs: slideCs, bbox: { x: 0, y: 0, width: 220, height: 357 } },
+      }, [child]);
+    };
+    const trackCs = { display: "flex", position: "static" };
+    const track = xNode("n1", "ul", {
+      375: { cs: trackCs, bbox: { x: 0, y: 0, width: 375, height: 357 } },
+      768: { cs: trackCs, bbox: { x: 0, y: 0, width: 768, height: 357 } },
+      1280: { cs: trackCs, bbox: { x: 0, y: 0, width: 1280, height: 357 } },
+    }, [mkSlide("n2", "n3"), mkSlide("n4", "n5")]);
+    return xNode("n0", "body", {
+      375: { bbox: { x: 0, y: 0, width: 375, height: 357 } },
+      768: { bbox: { x: 0, y: 0, width: 768, height: 357 } },
+      1280: { bbox: { x: 0, y: 0, width: 1280, height: 357 } },
+    }, [track]);
+  }
+
+  it("pins the slide's captured width even though its block child reports wAuto:true", () => {
+    const css = generateCss(xIr(slideRow()), new Map());
+    const slide = allRulesX(css, "n2");
+    assert.ok(/width:220px/.test(slide), `the library-sized slide must keep its 220px width, got: ${slide}`);
+  });
+});
+
+// FIX 4b — the circular-slide detector must NOT misfire on a genuine fluid full-bleed section. A
+// `shrink-0` flex/grid item whose box spans the FULL viewport at ≥2 distinct captured widths (x≈0,
+// width≈vp) with zero horizontal margins provably HAS a width source (it fills a fluid container /
+// was authored width:100%) — there is no circular collapse, so it must emit a fluid width, not freeze
+// to per-breakpoint captured px (w-320/w-192/w-480). Same "proven fluid" bar (≥2 distinct widths).
+describe("generateCss circular-slide guard skips fluid full-bleed section (FIX 4b)", () => {
+  const blockFill = (): RawSizing => ({ wAuto: true, wFill: true, hAuto: true, hFill: true });
+  function fullBleedSection() {
+    // A shrink-0 flex item whose bbox tracks the viewport (375/768/1280) with zero horizontal margins:
+    // a fluid full-bleed section, NOT a fixed-width carousel slide. Its block child fills it.
+    const child = xNode("n2", "div", {
+      375: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 375, height: 80 }, sizing: blockFill() },
+      768: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 768, height: 80 }, sizing: blockFill() },
+      1280: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 1280, height: 80 }, sizing: blockFill() },
+    }, [{ text: "Full bleed" } as IRChild]);
+    // flex-shrink:0 item; its captured px equals the viewport at each width (what the library/probe saw).
+    // boxSizing:content-box keeps isFillsContainerWidth/isFullWidthShrinkSlide (border-box only) off, so
+    // WITHOUT the guard the circular-slide detector wins and freezes these per-breakpoint px.
+    const secCs = (w: number) => ({ display: "block", position: "static", flexShrink: "0", boxSizing: "content-box", marginLeft: "0px", marginRight: "0px", width: `${w}px` });
+    const section = xNode("n1", "nav", {
+      375: { cs: secCs(375), bbox: { x: 0, y: 0, width: 375, height: 80 } },
+      768: { cs: secCs(768), bbox: { x: 0, y: 0, width: 768, height: 80 } },
+      1280: { cs: secCs(1280), bbox: { x: 0, y: 0, width: 1280, height: 80 } },
+    }, [child]);
+    // A flex track with symmetric padding: its CONTENT width is narrower than the full-viewport section,
+    // so the "fills the flex container content" detectors (isFillsContainerWidth / isFullWidthShrinkSlide)
+    // do NOT fire — leaving the circular-slide detector as the width-plan winner it must be guarded from.
+    const trackCs = { display: "flex", position: "static", paddingLeft: "24px", paddingRight: "24px" };
+    return xNode("n0", "body", {
+      375: { cs: trackCs, bbox: { x: 0, y: 0, width: 375, height: 80 } },
+      768: { cs: trackCs, bbox: { x: 0, y: 0, width: 768, height: 80 } },
+      1280: { cs: trackCs, bbox: { x: 0, y: 0, width: 1280, height: 80 } },
+    }, [section]);
+  }
+
+  it("emits a fluid width for a full-viewport-span shrink-0 flex item, not frozen per-breakpoint px", () => {
+    const css = generateCss(xIr(fullBleedSection()), new Map());
+    const section = allRulesX(css, "n1");
+    assert.ok(!/width:375px|width:768px|width:1280px/.test(section), `a fluid full-bleed section must not freeze to captured px, got: ${section}`);
+    // A fluid outcome is either an explicit fluid width (width:100%/auto) OR no width at all — the block
+    // default resolves to auto and fills the container. Any FIXED px width would be the frozen misfire.
+    assert.ok(!/width:\d/.test(section) || /width:100%|width:auto/.test(section), `a fluid full-bleed section must emit a fluid width (or none), got: ${section}`);
+  });
+});
+
+// ===========================================================================
+// Emission-geometry fix wave (T1/T2/T3/T5, C1 css side, C2)
+// ===========================================================================
+
+// T5 — a FULL-WIDTH block merely inset by a fixed gutter (`mx-4 md:mx-8`: box == container − 2·gutter,
+// width TRACKS the container) must NOT be auto-centred. Its symmetric margins vary per breakpoint and
+// the probe reads wAuto (auto reproduces the inset width), so it slips past the fill guard — but
+// emitting margin:auto on a width-dropped block resolves the margins to 0 and blows it full-bleed.
+describe("generateCss auto-margin gutter-inset guard (T5)", () => {
+  const auto = (): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false });
+  it("keeps literal px margins on a full-width gutter-inset block (width tracks the container)", () => {
+    // mx-4 (16px) mobile, mx-8 (32px) desktop: box width == container − 2·gutter at every width, so it
+    // TRACKS the container (343→704→1216). Not a centred content box.
+    const child = xNode("n1", "div", {
+      375: { cs: { display: "block", marginLeft: "16px", marginRight: "16px", width: "343px" }, bbox: { x: 16, y: 0, width: 343, height: 40 }, sizing: auto() },
+      768: { cs: { display: "block", marginLeft: "32px", marginRight: "32px", width: "704px" }, bbox: { x: 32, y: 0, width: 704, height: 40 }, sizing: auto() },
+      1280: { cs: { display: "block", marginLeft: "32px", marginRight: "32px", width: "1216px" }, bbox: { x: 32, y: 0, width: 1216, height: 40 }, sizing: auto() },
+    });
+    const parent = xNode("n0", "body", {
+      375: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 375, height: 40 } },
+      768: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 768, height: 40 } },
+      1280: { cs: { display: "block" }, bbox: { x: 0, y: 0, width: 1280, height: 40 } },
+    }, [child]);
+    const css = generateCss(xIr(parent), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/margin-left:auto/.test(all), `a gutter-inset full-width block must not be auto-centred, got: ${all}`);
+    assert.ok(/margin-left:16px|margin-left:32px/.test(all), `it must keep its literal px margins, got: ${all}`);
+  });
+});
+
+// T3 — an authored height whose OWN probe says hAuto:false && hFill:false is load-bearing. The
+// structural "taller than content" tests can't fire when an inline child's extent equals the box, so
+// emission must trust the node's own probe (the twin of the heightFlows keep) and emit the height.
+describe("generateCss authored-height kept via own probe (T3)", () => {
+  it("emits the height when the node's own probe is hAuto:false, hFill:false", () => {
+    const explicit = (): RawSizing => ({ wAuto: false, wFill: false, hAuto: false, hFill: false });
+    // Wrapper's only in-flow child is an inline <a> whose box equals the wrapper (content extent ==
+    // box height), so neither the taller-than-content nor overflow test can fire.
+    const link = xNode("n2", "a", {
+      375: { cs: { display: "inline", position: "static" }, bbox: { x: 0, y: 0, width: 220, height: 300 } },
+      768: { cs: { display: "inline", position: "static" }, bbox: { x: 0, y: 0, width: 220, height: 300 } },
+      1280: { cs: { display: "inline", position: "static" }, bbox: { x: 0, y: 0, width: 220, height: 300 } },
+    }, [{ text: "shop" } as IRChild]);
+    const wrapper = xNode("n1", "div", {
+      375: { cs: { display: "block", position: "static", height: "300px" }, bbox: { x: 0, y: 0, width: 220, height: 300 }, sizing: explicit() },
+      768: { cs: { display: "block", position: "static", height: "300px" }, bbox: { x: 0, y: 0, width: 220, height: 300 }, sizing: explicit() },
+      1280: { cs: { display: "block", position: "static", height: "300px" }, bbox: { x: 0, y: 0, width: 220, height: 300 }, sizing: explicit() },
+    }, [link]);
+    const parent = xNode("n0", "body", {
+      375: { bbox: { x: 0, y: 0, width: 375, height: 300 } },
+      768: { bbox: { x: 0, y: 0, width: 768, height: 300 } },
+      1280: { bbox: { x: 0, y: 0, width: 1280, height: 300 } },
+    }, [wrapper]);
+    const css = generateCss(xIr(parent), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(/height:300px/.test(all), `authored height must survive on own-probe evidence, got: ${all}`);
+  });
+});
+
+// R2 — the own-probe height trust (T3) must NEVER bake a document-height wrapper. A body/html/main
+// landmark, or any node whose captured box IS the page scroll height, probes hAuto:false/hFill:false
+// as document-level re-measure noise (min-h-screen + %-height chain), not an authored height. Baking
+// it pins the page to a fixed height — which, under an overflow:hidden main, hard-clips content drift
+// and blinds the layout gate's heightDelta. Such wrappers must keep flowing (auto height).
+describe("generateCss own-probe height trust never bakes a page-height wrapper (R2)", () => {
+  const explicit = (): RawSizing => ({ wAuto: false, wFill: false, hAuto: false, hFill: false });
+  // xIr sets perViewport.scrollHeight = 800 at every viewport.
+  function pageWrapper(tag: string, h: number) {
+    // A non-leaf wrapper with an in-flow child, whose own probe reads authored (hAuto/hFill false).
+    const child = xNode("n2", "div", Object.fromEntries(XVPS.map((vp) => [vp, { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: vp, height: h } }])));
+    const wrap = xNode("n1", tag, Object.fromEntries(XVPS.map((vp) => [vp, { cs: { display: "block", position: "static", height: `${h}px` }, bbox: { x: 0, y: 0, width: vp, height: h }, sizing: explicit() }])), [child]);
+    return xNode("n0", "body", Object.fromEntries(XVPS.map((vp) => [vp, { bbox: { x: 0, y: 0, width: vp, height: h } }])), [wrap]);
+  }
+
+  it("does NOT bake a <main> landmark height even when its own probe is authored", () => {
+    const css = generateCss(xIr(pageWrapper("main", 800)), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/height:800px/.test(all), `main landmark must keep flowing, got: ${all}`);
+  });
+
+  it("does NOT bake a wrapper whose captured height IS the page scroll height (±2%)", () => {
+    // 792 is within 2% of the 800px scrollHeight — a page-height wrapper, not authored content.
+    const css = generateCss(xIr(pageWrapper("div", 792)), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/height:792px/.test(all), `near-page-height wrapper must keep flowing, got: ${all}`);
+  });
+
+  it("still bakes a genuinely authored height well below the page height", () => {
+    // 300px is far from the 800px scrollHeight — a real authored box (the T3 case) still survives.
+    const css = generateCss(xIr(pageWrapper("div", 300)), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(/height:300px/.test(all), `authored sub-page height must still survive, got: ${all}`);
+  });
+});
+
+// FIX 1 — a banded AUTHORED fixed height (`h-[4rem] sm:h-[4.5rem] md:h-[6.25rem]`) on a grid/flex item
+// whose fill child reproduces the box height (the fill↔content cycle: hFill:true) must NOT collapse to
+// `height:100%`. The source authors a definite per-band height, geometry corroborates it (computed px ==
+// bbox at every vp), so the baked per-band px must survive instead of the probe's circular fill verdict.
+describe("generateCss authored banded fixed height survives the fill cycle (FIX 1)", () => {
+  const cycle = (): RawSizing => ({ wAuto: false, wFill: true, hAuto: false, hFill: true });
+  function tile(): IRNode {
+    // Inner filler: height:100% child (the fill side of the cycle).
+    const inner = xNode("n2", "span", Object.fromEntries(XVPS.map((vp) => [vp, {
+      cs: { display: "block", position: "static", height: "100%" },
+      bbox: { x: 0, y: 0, width: 100, height: vp === 375 ? 60 : vp === 768 ? 93.75 : 100 },
+    }])));
+    const t = xNode("n1", "div", {
+      375: { cs: { display: "flex", position: "static", height: "60px" }, bbox: { x: 0, y: 0, width: 100, height: 60 }, sizing: cycle() },
+      768: { cs: { display: "flex", position: "static", height: "93.75px" }, bbox: { x: 0, y: 0, width: 100, height: 93.75 }, sizing: cycle() },
+      1280: { cs: { display: "flex", position: "static", height: "100px" }, bbox: { x: 0, y: 0, width: 100, height: 100 }, sizing: cycle() },
+    }, [inner]);
+    t.srcClass = "px-2 flex h-[4rem] w-full items-center justify-center sm:h-[4.5rem] md:h-[6.25rem]";
+    // Grid parent that confers a definite height at every band, so isHeightFill/heightProbeFills would
+    // otherwise drop the tile to h-full.
+    return xNode("n0", "div", {
+      375: { cs: { display: "grid", position: "static", height: "60px" }, bbox: { x: 0, y: 0, width: 375, height: 60 } },
+      768: { cs: { display: "grid", position: "static", height: "93.75px" }, bbox: { x: 0, y: 0, width: 768, height: 93.75 } },
+      1280: { cs: { display: "grid", position: "static", height: "100px" }, bbox: { x: 0, y: 0, width: 1280, height: 100 } },
+    }, [t]);
+  }
+
+  it("keeps the baked per-band px height and never emits height:100%", () => {
+    const css = generateCss(xIr(tile()), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/height:100%/.test(all), `authored fixed-height tile must not collapse to h-full, got: ${all}`);
+    assert.ok(/height:60px/.test(all), `375 band height (60px) must survive, got: ${all}`);
+    assert.ok(/height:93\.75px/.test(all), `768 band height (93.75px) must survive, got: ${all}`);
+    assert.ok(/height:100px/.test(all), `desktop band height (100px) must survive, got: ${all}`);
+  });
+});
+
+// FIX 3 — a testimonial-avatar wrapper authors a fixed square (`h-[2.5rem] w-[2.5rem] shrink-0`) whose
+// img child fills it, so the sizing probe reads hAuto/wAuto:true and would drop BOTH dimensions, letting
+// the box collapse to the img's intrinsic size. With geometry corroboration (computed px == bbox at
+// every vp), the authored fixed width AND height must be emitted.
+describe("generateCss authored fixed avatar size survives the content drop (FIX 3)", () => {
+  const drop = (): RawSizing => ({ wAuto: true, wFill: false, hAuto: true, hFill: false });
+  function avatar(): IRNode {
+    const img = xNode("n2", "img", Object.fromEntries(XVPS.map((vp) => [vp, {
+      cs: { display: "block", position: "static", height: "100%", width: "100%" },
+      bbox: { x: 0, y: 0, width: vp === 1280 ? 40 : 37.5, height: vp === 1280 ? 40 : 37.5 },
+    }])));
+    const a = xNode("n1", "div", {
+      375: { cs: { display: "block", position: "static", height: "37.5px", width: "37.5px" }, bbox: { x: 0, y: 0, width: 37.5, height: 37.5 }, sizing: drop() },
+      768: { cs: { display: "block", position: "static", height: "37.5px", width: "37.5px" }, bbox: { x: 0, y: 0, width: 37.5, height: 37.5 }, sizing: drop() },
+      1280: { cs: { display: "block", position: "static", height: "40px", width: "40px" }, bbox: { x: 0, y: 0, width: 40, height: 40 }, sizing: drop() },
+    }, [img]);
+    a.srcClass = "avatar-border-container h-[2.5rem] w-[2.5rem] shrink-0";
+    return xNode("n0", "div", Object.fromEntries(XVPS.map((vp) => [vp, { cs: { display: "flex", position: "static" }, bbox: { x: 0, y: 0, width: vp, height: 40 } }])), [a]);
+  }
+
+  it("emits both the authored fixed width and height per band", () => {
+    const css = generateCss(xIr(avatar()), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(/width:37\.5px/.test(all), `narrow-band width (37.5px) must survive, got: ${all}`);
+    assert.ok(/height:37\.5px/.test(all), `narrow-band height (37.5px) must survive, got: ${all}`);
+    assert.ok(/width:40px/.test(all), `desktop width (40px) must survive, got: ${all}`);
+    assert.ok(/height:40px/.test(all), `desktop height (40px) must survive, got: ${all}`);
+  });
+});
+
+// FIX 2 — aspectHeightLaw must account for the aspect-ratio↔max-height WIDTH transfer. At a
+// max-height-clamped viewport, choosing a ratio also caps the width at ratio×maxH; a square ratio for a
+// 1.66:1 box (w=698, h=maxH=420) satisfies the height-only check but would clamp the clone's width to
+// 420. The law must reject that ratio (and fall back to explicit per-band dimensions) rather than emit a
+// wrong aspect-square.
+describe("generateCss aspectHeightLaw rejects width-clamping ratio transfer (FIX 2)", () => {
+  function photo(): IRNode {
+    // 375: genuinely square, unclamped (304.69²). 768: 1.66:1 but height clamped to max-h 420 (w=698).
+    // 1280: genuinely square, unclamped (372²). The 768 clamp must not license aspect-square.
+    // Single-row grid (grid-template-rows == content height) so singleFluidGridRow fires and the
+    // media/aspect pass runs.
+    const container = xNode("n1", "div", {
+      375: { cs: { display: "grid", position: "static", maxHeight: "420px", aspectRatio: "auto", gridTemplateRows: "304.69px" }, bbox: { x: 0, y: 0, width: 304.69, height: 304.69 } },
+      768: { cs: { display: "grid", position: "static", maxHeight: "420px", aspectRatio: "auto", gridTemplateRows: "420px" }, bbox: { x: 0, y: 0, width: 697.69, height: 420 } },
+      1280: { cs: { display: "grid", position: "static", maxHeight: "none", aspectRatio: "auto", gridTemplateRows: "371.66px" }, bbox: { x: 0, y: 0, width: 371.66, height: 371.66 } },
+    });
+    return xNode("n0", "div", Object.fromEntries(XVPS.map((vp) => [vp, { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: vp, height: 500 } }])), [container]);
+  }
+
+  it("does not emit aspect-square for a box whose max-height clamp would shrink its width", () => {
+    const css = generateCss(xIr(photo()), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/aspect-ratio:\s*1\s*\/\s*1/.test(all) && !/aspect-ratio:1\/1/.test(all),
+      `must not force aspect-square where the max-height transfer would clamp width, got: ${all}`);
+  });
+});
+
+// FIX 4 — a full-screen hero authored `min-h-[100vh] md:min-h-[calc(100vh - 137px)]` gets its
+// per-viewport min-height baked to px at capture, freezing the hero to one window height and leaving
+// whitespace at other heights. With an authored vh-token corroboration, the constant-offset law
+// `calc(100vh - 137px)` (k=1) must be recovered from samples spanning DIFFERENT viewport heights and
+// re-emitted, instead of the frozen px. XVPS heights are 812/1024/800, so C=137 → 675/887/663px.
+describe("generateCss recovers a viewport-relative min-height law (FIX 4)", () => {
+  function hero(src: string | undefined): IRNode {
+    const n = xNode("n1", "section", {
+      375: { cs: { display: "flex", position: "static", minHeight: "675px" }, bbox: { x: 0, y: 0, width: 375, height: 675 } },
+      768: { cs: { display: "flex", position: "static", minHeight: "887px" }, bbox: { x: 0, y: 0, width: 768, height: 887 } },
+      1280: { cs: { display: "flex", position: "static", minHeight: "663px" }, bbox: { x: 0, y: 0, width: 1280, height: 663 } },
+    });
+    if (src !== undefined) n.srcClass = src;
+    return xNode("n0", "body", Object.fromEntries(XVPS.map((vp) => [vp, { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: vp, height: 900 } }])), [n]);
+  }
+
+  it("emits calc(100vh - 137px) and drops the frozen px when srcClass carries a vh token", () => {
+    const css = generateCss(xIr(hero("flex min-h-[100vh] md:min-h-[calc(100vh_-_137px)]")), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(/min-height:calc\(100vh - 137px\)/.test(all), `hero min-height must become the viewport law, got: ${all}`);
+    assert.ok(!/min-height:663px/.test(all), `desktop min-height must not stay frozen px, got: ${all}`);
+    assert.ok(!/min-height:887px/.test(all), `768 min-height must not stay frozen px, got: ${all}`);
+    assert.ok(!/min-height:675px/.test(all), `375 min-height must not stay frozen px, got: ${all}`);
+  });
+
+  it("keeps the baked px when srcClass has NO viewport-relative token (corroboration guard)", () => {
+    const css = generateCss(xIr(hero("flex min-h-[675px] md:min-h-[663px]")), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/calc\(100vh/.test(all), `a content-driven min-height must not be mistaken for a vh law, got: ${all}`);
+    assert.ok(/min-height:663px/.test(all) || /min-height:675px/.test(all) || /min-height:887px/.test(all),
+      `without a vh token the baked px min-height must survive, got: ${all}`);
+  });
+});
+
+// C1 (css side) — a computed `grid-template-rows: subgrid` is a STRUCTURAL keyword, not a baked px
+// regime. It must NEVER be dropped by the reflow-mode dropGridRows path (which strips px row tracks).
+describe("collectNodeRules never drops a subgrid rows template (C1)", () => {
+  function gridFixture() {
+    const layer = xNode("n2", "a", {
+      375: { cs: { display: "grid", position: "static", gridTemplateRows: "subgrid" }, bbox: { x: 0, y: 0, width: 375, height: 400 } },
+      768: { cs: { display: "grid", position: "static", gridTemplateRows: "subgrid" }, bbox: { x: 0, y: 0, width: 768, height: 400 } },
+      1280: { cs: { display: "grid", position: "static", gridTemplateRows: "subgrid" }, bbox: { x: 0, y: 0, width: 1280, height: 400 } },
+    });
+    const outer = xNode("n1", "div", {
+      375: { cs: { display: "grid", position: "static", gridTemplateRows: "139px 717px" }, bbox: { x: 0, y: 0, width: 375, height: 856 } },
+      768: { cs: { display: "grid", position: "static", gridTemplateRows: "139px 717px" }, bbox: { x: 0, y: 0, width: 768, height: 856 } },
+      1280: { cs: { display: "grid", position: "static", gridTemplateRows: "340px 340px" }, bbox: { x: 0, y: 0, width: 1280, height: 680 } },
+    }, [layer]);
+    return xNode("n0", "body", {
+      375: { bbox: { x: 0, y: 0, width: 375, height: 856 } },
+      768: { bbox: { x: 0, y: 0, width: 768, height: 856 } },
+      1280: { bbox: { x: 0, y: 0, width: 1280, height: 680 } },
+    }, [outer]);
+  }
+
+  it("emits grid-template-rows:subgrid even in reflow mode", () => {
+    const rules = collectNodeRules(xIr(gridFixture()), new Map(), undefined, undefined, undefined, true);
+    const nr = rules.get("n2");
+    assert.ok(nr, "subgrid layer rule must exist");
+    const all = [nr!.base.get("grid-template-rows"), ...nr!.bands.map((b) => b.decls.get("grid-template-rows"))].filter(Boolean).join(";");
+    assert.ok(/subgrid/.test(all), `subgrid keyword must survive reflow dropGridRows, got: ${all}`);
+  });
+});
+
+// C2 — a grid ITEM's `%` width resolves against its GRID AREA (track), not the grid container's
+// content box. For a multi-column grid the parent-content-box ratio is the wrong base, so the fluid
+// per-band percent path must BAIL (the item falls to auto/fixed) rather than emit a collapsing %.
+describe("generateCss grid-item percent width bails to track (C2)", () => {
+  function gridItemFixture() {
+    // 4-column grid: each track ~302px. The item's width == its track (varies with the container), so
+    // fluidPercentByVp would compute ~24.5% of the 1240px content box — wrong (browser applies it to
+    // the 302px track → 74px). Must not emit a percent width.
+    const item = xNode("n2", "div", {
+      375: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 343, height: 108 } },
+      768: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 176, height: 108 } },
+      1280: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 302, height: 108 } },
+    }, [{ text: "changelog card" } as IRChild]);
+    const grid = xNode("n1", "div", {
+      375: { cs: { display: "grid", position: "static", gridTemplateColumns: "343px" }, bbox: { x: 0, y: 0, width: 375, height: 108 } },
+      768: { cs: { display: "grid", position: "static", gridTemplateColumns: "176px 176px 176px" }, bbox: { x: 0, y: 0, width: 768, height: 108 } },
+      1280: { cs: { display: "grid", position: "static", gridTemplateColumns: "302px 302px 302px 302px" }, bbox: { x: 0, y: 0, width: 1240, height: 108 } },
+    }, [item]);
+    return xNode("n0", "body", {
+      375: { bbox: { x: 0, y: 0, width: 375, height: 108 } },
+      768: { bbox: { x: 0, y: 0, width: 768, height: 108 } },
+      1280: { bbox: { x: 0, y: 0, width: 1280, height: 108 } },
+    }, [grid]);
+  }
+
+  it("does not emit a container-content-box percent width for a multi-column grid item", () => {
+    const css = generateCss(xIr(gridItemFixture()), new Map());
+    const all = allRulesX(css, "n2");
+    assert.ok(!/width:24\.5%|width:24%/.test(all), `grid item must not resolve % against the wrong containing block, got: ${all}`);
+  });
+});
+
+// T1 — an off-screen-right (invisible-by-vp) in-flow flex slide still OCCUPIES layout and sets its
+// track's cross-size. The base rule bakes canonical (desktop) geometry; without a per-viewport delta
+// the frozen desktop width inflates the mobile track. The band must carry the slide's measured
+// per-viewport geometry, not just a hide.
+describe("collectNodeRules off-screen in-flow slide per-viewport geometry (T1)", () => {
+  function carousel() {
+    // Slide is visible at 1280 (285px desktop) but off-screen-right at 375 (invisible-by-vp, measured
+    // 220px). It is in-flow (static), display:block, non-zero bbox at 375 — occupying.
+    const slide = xNode("n2", "li", {
+      375: { cs: { display: "block", position: "static", flexShrink: "0", width: "220px", opacity: "1" }, bbox: { x: 400, y: 0, width: 220, height: 300 }, visible: false },
+      768: { cs: { display: "block", position: "static", flexShrink: "0", width: "220px", opacity: "1" }, bbox: { x: 500, y: 0, width: 220, height: 300 }, visible: false },
+      1280: { cs: { display: "block", position: "static", flexShrink: "0", width: "285px", opacity: "1" }, bbox: { x: 0, y: 0, width: 285, height: 400 }, visible: true },
+    }, [{ text: "slide" } as IRChild]);
+    const track = xNode("n1", "ul", {
+      375: { cs: { display: "flex", position: "static" }, bbox: { x: 0, y: 0, width: 375, height: 300 } },
+      768: { cs: { display: "flex", position: "static" }, bbox: { x: 0, y: 0, width: 768, height: 300 } },
+      1280: { cs: { display: "flex", position: "static" }, bbox: { x: 0, y: 0, width: 1280, height: 400 } },
+    }, [slide]);
+    return xNode("n0", "body", {
+      375: { bbox: { x: 0, y: 0, width: 375, height: 300 } },
+      768: { bbox: { x: 0, y: 0, width: 768, height: 300 } },
+      1280: { bbox: { x: 0, y: 0, width: 1280, height: 400 } },
+    }, [track]);
+  }
+
+  it("emits a per-viewport width delta for the off-screen slide (not just a hide)", () => {
+    const rules = collectNodeRules(xIr(carousel()), new Map());
+    const nr = rules.get("n2");
+    assert.ok(nr, "slide rule must exist");
+    // The narrow band must carry the measured 220px width, overriding the baked 285px desktop base.
+    const narrowBand = nr!.bands.find((b) => /max-width/.test(b.media) && b.decls.has("width"));
+    assert.ok(narrowBand, `off-screen slide must get a per-viewport width delta, got bands: ${JSON.stringify(nr!.bands.map((b) => ({ m: b.media, w: b.decls.get("width") })))}`);
+    assert.equal(narrowBand!.decls.get("width"), "220px", "the band carries the measured narrow-vp width");
+  });
+});
+
+// T2 — an authored parent height whose only in-flow child is an UN-PROBED <picture>/object-fit:cover
+// replaced element that FILLS the box (border-box == parent content box) must be treated as a
+// height-deriving fill child (so the authored height is kept, not dropped as content-derived).
+describe("collectNodeRules picture fill child keeps authored height (T2)", () => {
+  function heroFixture() {
+    const explicitH = (): RawSizing => ({ wAuto: false, wFill: true, hAuto: false, hFill: false });
+    // <picture> is a replaced tag the probe skips → no sizing; its border-box == the wrapper content
+    // box at every vp. Height varies across vps so the flow path would otherwise try to drop it.
+    const picture = xNode("n2", "picture", {
+      375: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 375, height: 560 } },
+      768: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 768, height: 500 } },
+      1280: { cs: { display: "block", position: "static" }, bbox: { x: 0, y: 0, width: 1280, height: 480 } },
+    });
+    const wrapper = xNode("n1", "div", {
+      375: { cs: { display: "block", position: "static", height: "560px" }, bbox: { x: 0, y: 0, width: 375, height: 560 }, sizing: explicitH() },
+      768: { cs: { display: "block", position: "static", height: "500px" }, bbox: { x: 0, y: 0, width: 768, height: 500 }, sizing: explicitH() },
+      1280: { cs: { display: "block", position: "static", height: "480px" }, bbox: { x: 0, y: 0, width: 1280, height: 480 }, sizing: explicitH() },
+    }, [picture]);
+    return xNode("n0", "body", {
+      375: { bbox: { x: 0, y: 0, width: 375, height: 560 } },
+      768: { bbox: { x: 0, y: 0, width: 768, height: 500 } },
+      1280: { bbox: { x: 0, y: 0, width: 1280, height: 480 } },
+    }, [wrapper]);
+  }
+
+  it("keeps the wrapper's authored height when a <picture> child fills it", () => {
+    const rules = collectNodeRules(xIr(heroFixture()), new Map());
+    const nr = rules.get("n1");
+    assert.ok(nr, "wrapper rule must exist");
+    const all = [nr!.base.get("height"), ...nr!.bands.map((b) => b.decls.get("height"))].filter(Boolean).join(";");
+    assert.ok(/560px|500px|480px/.test(all), `authored height must survive with a picture fill child, got: ${all}`);
+  });
+});
+
+// A `position:sticky` full-width banner wrapper: its box spans the viewport at EVERY captured width
+// (375/768/1280), so it was authored fluid (width:100%/auto) — sticky only shifts the box's offset
+// while scrolling, never its resolved width. Freezing it to the canonical 1280px means at a 375
+// viewport its `justify-content:center` pushes the inner content off-screen. A viewport-tracking
+// sticky wrapper must emit no frozen width (→ fluid `width:auto`, resolving to the identical px at
+// every captured width, so gates 0–6 stay unmoved).
+describe("generateCss sticky full-width wrapper is viewport-tracking (no px freeze)", () => {
+  // Sticky banner directly under <body>; spans the full viewport width at every width, centred inner.
+  function stickyBanner() {
+    const inner = xNode("n2", "span", {
+      375: { cs: { display: "inline-block" }, bbox: { x: 120, y: 8, width: 135, height: 20 } },
+      768: { cs: { display: "inline-block" }, bbox: { x: 316, y: 8, width: 135, height: 20 } },
+      1280: { cs: { display: "inline-block" }, bbox: { x: 572, y: 8, width: 135, height: 20 } },
+    }, [{ text: "Enrollment is open" } as IRChild]);
+    const banner = xNode("n1", "div", {
+      375: { cs: { display: "flex", position: "sticky", justifyContent: "center", top: "0px", width: "375px" }, bbox: { x: 0, y: 0, width: 375, height: 36 } },
+      768: { cs: { display: "flex", position: "sticky", justifyContent: "center", top: "0px", width: "768px" }, bbox: { x: 0, y: 0, width: 768, height: 36 } },
+      1280: { cs: { display: "flex", position: "sticky", justifyContent: "center", top: "0px", width: "1280px" }, bbox: { x: 0, y: 0, width: 1280, height: 36 } },
+    }, [inner]);
+    return xNode("n0", "body", {
+      375: { bbox: { x: 0, y: 0, width: 375, height: 800 } },
+      768: { bbox: { x: 0, y: 0, width: 768, height: 800 } },
+      1280: { bbox: { x: 0, y: 0, width: 1280, height: 800 } },
+    }, [banner]);
+  }
+
+  it("does not freeze the sticky banner width to the canonical px", () => {
+    const css = generateCss(xIr(stickyBanner()), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/width:1280px/.test(all), `sticky full-width banner must not freeze to canonical px, got: ${all}`);
+    assert.ok(!/width:768px/.test(all) && !/width:375px/.test(all), `no per-band px freeze either, got: ${all}`);
+  });
+
+  it("does not inject auto margins (fix drops the width only, not centring)", () => {
+    // The d3ec154 guard: mx-auto only for true auto-margin centring. A sticky banner centres its
+    // INNER content via justify-content, so the wrapper itself must not gain auto side margins.
+    const css = generateCss(xIr(stickyBanner()), new Map());
+    const all = allRulesX(css, "n1");
+    assert.ok(!/margin-left:auto/.test(all) && !/margin-right:auto/.test(all), `must not add auto margins, got: ${all}`);
+  });
+
+  it("still freezes a genuinely fixed-width sticky element (not viewport-spanning)", () => {
+    // A sticky sidebar rail whose width is a real fixed px (constant 280px, never == the viewport)
+    // must keep its baked width — the fluid-full-bleed detector only fires when the box spans the
+    // viewport at every width.
+    const rail = xNode("n1", "div", {
+      375: { cs: { display: "block", position: "sticky", top: "0px", width: "280px" }, bbox: { x: 0, y: 0, width: 280, height: 400 } },
+      768: { cs: { display: "block", position: "sticky", top: "0px", width: "280px" }, bbox: { x: 0, y: 0, width: 280, height: 400 } },
+      1280: { cs: { display: "block", position: "sticky", top: "0px", width: "280px" }, bbox: { x: 0, y: 0, width: 280, height: 400 } },
+    });
+    const root = xNode("n0", "body", {
+      375: { bbox: { x: 0, y: 0, width: 375, height: 800 } },
+      768: { bbox: { x: 0, y: 0, width: 768, height: 800 } },
+      1280: { bbox: { x: 0, y: 0, width: 1280, height: 800 } },
+    }, [rail]);
+    const css = generateCss(xIr(root), new Map());
+    assert.ok(/width:280px/.test(allRulesX(css, "n1")), `a fixed-width sticky rail keeps its px, got: ${allRulesX(css, "n1")}`);
+  });
+});
diff --git a/compiler/test/dotlottie.test.ts b/compiler/test/dotlottie.test.ts
new file mode 100644
index 0000000..e7e607a
--- /dev/null
+++ b/compiler/test/dotlottie.test.ts
@@ -0,0 +1,146 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { deflateRawSync } from "node:zlib";
+import { isZipArchive, extractDotLottieJson, readZipEntry } from "../src/capture/dotlottie.js";
+import { extFromUrl } from "../src/capture/capture.js";
+
+/**
+ * Build a minimal, spec-correct ZIP archive in-memory from named entries. Supports both
+ * stored (method 0) and deflated (method 8) compression so the extractor is exercised on both.
+ * No CRC validation is needed for our reader, so CRC fields are left 0.
+ */
+function buildZip(entries: Array<{ name: string; data: Buffer; deflate?: boolean }>): Buffer {
+  const locals: Buffer[] = [];
+  const centrals: Buffer[] = [];
+  let offset = 0;
+
+  for (const e of entries) {
+    const nameBuf = Buffer.from(e.name, "utf8");
+    const stored = e.deflate ? deflateRawSync(e.data) : e.data;
+    const method = e.deflate ? 8 : 0;
+
+    const local = Buffer.alloc(30 + nameBuf.length);
+    local.writeUInt32LE(0x04034b50, 0); // local file header sig
+    local.writeUInt16LE(20, 4); // version needed
+    local.writeUInt16LE(0, 6); // flags
+    local.writeUInt16LE(method, 8);
+    local.writeUInt16LE(0, 10); // time
+    local.writeUInt16LE(0, 12); // date
+    local.writeUInt32LE(0, 14); // crc
+    local.writeUInt32LE(stored.length, 18); // comp size
+    local.writeUInt32LE(e.data.length, 22); // uncomp size
+    local.writeUInt16LE(nameBuf.length, 26);
+    local.writeUInt16LE(0, 28); // extra len
+    nameBuf.copy(local, 30);
+    const localFull = Buffer.concat([local, stored]);
+    locals.push(localFull);
+
+    const central = Buffer.alloc(46 + nameBuf.length);
+    central.writeUInt32LE(0x02014b50, 0); // central dir sig
+    central.writeUInt16LE(20, 4); // version made by
+    central.writeUInt16LE(20, 6); // version needed
+    central.writeUInt16LE(0, 8); // flags
+    central.writeUInt16LE(method, 10);
+    central.writeUInt16LE(0, 12); // time
+    central.writeUInt16LE(0, 14); // date
+    central.writeUInt32LE(0, 16); // crc
+    central.writeUInt32LE(stored.length, 20); // comp size
+    central.writeUInt32LE(e.data.length, 24); // uncomp size
+    central.writeUInt16LE(nameBuf.length, 28);
+    central.writeUInt16LE(0, 30); // extra
+    central.writeUInt16LE(0, 32); // comment
+    central.writeUInt16LE(0, 34); // disk
+    central.writeUInt16LE(0, 36); // internal attrs
+    central.writeUInt32LE(0, 38); // external attrs
+    central.writeUInt32LE(offset, 42); // local header offset
+    nameBuf.copy(central, 46);
+    centrals.push(central);
+
+    offset += localFull.length;
+  }
+
+  const centralStart = offset;
+  const centralDir = Buffer.concat(centrals);
+  const eocd = Buffer.alloc(22);
+  eocd.writeUInt32LE(0x06054b50, 0);
+  eocd.writeUInt16LE(0, 4); // disk
+  eocd.writeUInt16LE(0, 6); // cd start disk
+  eocd.writeUInt16LE(entries.length, 8);
+  eocd.writeUInt16LE(entries.length, 10);
+  eocd.writeUInt32LE(centralDir.length, 12);
+  eocd.writeUInt32LE(centralStart, 16);
+  eocd.writeUInt16LE(0, 20); // comment len
+
+  return Buffer.concat([...locals, centralDir, eocd]);
+}
+
+const ANIM_1 = { v: "5.7.4", nm: "one", layers: [{ ind: 1 }] };
+const ANIM_2 = { v: "5.7.4", nm: "two", layers: [{ ind: 2 }] };
+const MANIFEST = { version: "1.0", animations: [{ id: "animation_default" }, { id: "animation_2" }] };
+
+describe("dotLottie ZIP extraction", () => {
+  it("detects ZIP archives by the PK local-header magic", () => {
+    assert.equal(isZipArchive(Buffer.from([0x50, 0x4b, 0x03, 0x04, 0, 0])), true);
+    assert.equal(isZipArchive(Buffer.from('{"v":"5.7"}', "utf8")), false);
+    assert.equal(isZipArchive(Buffer.alloc(2)), false);
+  });
+
+  it("extracts the manifest's default animation JSON from a stored dotLottie ZIP", () => {
+    const zip = buildZip([
+      { name: "manifest.json", data: Buffer.from(JSON.stringify(MANIFEST), "utf8") },
+      { name: "animations/animation_default.json", data: Buffer.from(JSON.stringify(ANIM_1), "utf8") },
+      { name: "animations/animation_2.json", data: Buffer.from(JSON.stringify(ANIM_2), "utf8") },
+    ]);
+    const out = extractDotLottieJson(zip);
+    assert.ok(out, "expected an extracted animation buffer");
+    assert.deepEqual(JSON.parse(out!.toString("utf8")), ANIM_1);
+  });
+
+  it("extracts a DEFLATE-compressed animation entry (the common real-world case)", () => {
+    const zip = buildZip([
+      { name: "manifest.json", data: Buffer.from(JSON.stringify(MANIFEST), "utf8"), deflate: true },
+      { name: "animations/animation_default.json", data: Buffer.from(JSON.stringify(ANIM_1), "utf8"), deflate: true },
+    ]);
+    const out = extractDotLottieJson(zip);
+    assert.ok(out);
+    assert.deepEqual(JSON.parse(out!.toString("utf8")), ANIM_1);
+  });
+
+  it("falls back to the name-sorted first animation when the manifest is absent", () => {
+    const zip = buildZip([
+      { name: "animations/b.json", data: Buffer.from(JSON.stringify(ANIM_2), "utf8") },
+      { name: "animations/a.json", data: Buffer.from(JSON.stringify(ANIM_1), "utf8") },
+    ]);
+    const out = extractDotLottieJson(zip);
+    assert.ok(out);
+    assert.deepEqual(JSON.parse(out!.toString("utf8")), ANIM_1); // "a.json" sorts first
+  });
+
+  it("returns null for non-ZIP bytes and for a ZIP with no animations", () => {
+    assert.equal(extractDotLottieJson(Buffer.from('{"v":"5.7"}', "utf8")), null);
+    const noAnims = buildZip([{ name: "manifest.json", data: Buffer.from("{}", "utf8") }]);
+    assert.equal(extractDotLottieJson(noAnims), null);
+  });
+
+  it("reads a named entry directly", () => {
+    const zip = buildZip([{ name: "manifest.json", data: Buffer.from(JSON.stringify(MANIFEST), "utf8"), deflate: true }]);
+    const m = readZipEntry(zip, "manifest.json");
+    assert.ok(m);
+    assert.deepEqual(JSON.parse(m!.toString("utf8")), MANIFEST);
+    assert.equal(readZipEntry(zip, "missing.json"), null);
+  });
+});
+
+describe("asset extension preservation (extFromUrl)", () => {
+  it("preserves real long extensions instead of truncating to 5 chars", () => {
+    assert.equal(extFromUrl("https://x/anim.lottie"), "lottie");
+    assert.equal(extFromUrl("https://x/site.webmanifest"), "webmanifest");
+    assert.equal(extFromUrl("https://x/pic.png?v=2"), "png");
+    assert.equal(extFromUrl("https://x/font.woff2"), "woff2");
+  });
+
+  it("rejects absurdly long or non-alphanumeric trailing segments", () => {
+    assert.equal(extFromUrl("https://x/name.thisisnotanextension"), "");
+    assert.equal(extFromUrl("https://x/dir.with.dots/file"), ""); // dot is in a path segment, not the file
+  });
+});
diff --git a/compiler/test/fontIntegrity.test.ts b/compiler/test/fontIntegrity.test.ts
new file mode 100644
index 0000000..5d48d51
--- /dev/null
+++ b/compiler/test/fontIntegrity.test.ts
@@ -0,0 +1,152 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { looksLikeFontFile } from "../src/capture/capture.js";
+import { buildFontGraph } from "../src/infer/fonts.js";
+import type { FontFace } from "../src/capture/walker.js";
+import type { AssetGraph, AssetEntry } from "../src/infer/assets.js";
+
+// --- Magic-byte validator table -------------------------------------------------------------
+
+function head(tag: string, len = 64): Buffer {
+  return Buffer.concat([Buffer.from(tag, "latin1"), Buffer.alloc(Math.max(0, len - tag.length))]);
+}
+
+describe("looksLikeFontFile (font container magic)", () => {
+  it("accepts every real font-container signature", () => {
+    assert.equal(looksLikeFontFile(head("wOF2")), true, "woff2");
+    assert.equal(looksLikeFontFile(head("wOFF")), true, "woff");
+    assert.equal(looksLikeFontFile(head("OTTO")), true, "CFF OpenType (otf)");
+    assert.equal(looksLikeFontFile(head("true")), true, "TrueType 'true' sfnt");
+    assert.equal(looksLikeFontFile(head("ttcf")), true, "TrueType collection");
+    assert.equal(
+      looksLikeFontFile(Buffer.concat([Buffer.from([0x00, 0x01, 0x00, 0x00]), Buffer.alloc(60)])),
+      true,
+      "TrueType \\x00\\x01\\x00\\x00 sfnt (ttf)",
+    );
+    // EOT: 0x504C ("LP") marker at byte offset 34.
+    const eot = Buffer.alloc(80);
+    eot[34] = 0x4c;
+    eot[35] = 0x50;
+    assert.equal(looksLikeFontFile(eot), true, "eot");
+  });
+
+  it("rejects HTML/text impostor bodies (the SPA-router 200 shell)", () => {
+    assert.equal(looksLikeFontFile(Buffer.from("<!DOCTYPE html><html><head></head></html>")), false);
+    assert.equal(looksLikeFontFile(Buffer.from("<!doctype html>")), false);
+    assert.equal(looksLikeFontFile(Buffer.from("<html><body>not a font</body></html>")), false);
+    assert.equal(looksLikeFontFile(Buffer.from("<?xml version=\"1.0\"?>")), false);
+    assert.equal(looksLikeFontFile(Buffer.from("just some plain text body")), false);
+  });
+
+  it("rejects truncated/empty buffers", () => {
+    assert.equal(looksLikeFontFile(Buffer.alloc(0)), false);
+    assert.equal(looksLikeFontFile(Buffer.from([0x77, 0x4f])), false); // 2 bytes of "wO"
+  });
+});
+
+// --- Validity-aware first-insert preference in buildFontGraph -------------------------------
+
+function fontEntry(sourceUrl: string, localPath: string | null): AssetEntry {
+  return {
+    sourceUrl,
+    type: "font",
+    classification: localPath ? "downloaded" : "skipped",
+    localPath,
+    storedFile: localPath ? localPath.split("/").pop()! : null,
+    bytes: localPath ? 45_000 : 0,
+    reason: localPath ? null : "font_file_unavailable",
+    impact: null,
+    via: [],
+  };
+}
+
+function graphOf(entries: AssetEntry[]): AssetGraph {
+  const byUrl = new Map<string, AssetEntry>();
+  for (const e of entries) byUrl.set(e.sourceUrl, e);
+  return { entries, byUrl };
+}
+
+const DOC = "https://host.example/page";
+// The genuine subset lives under the css file's sibling media dir; only THIS url is downloaded.
+const GOOD_URL = "https://host.example/marketing-static/_next/static/media/good.woff2";
+// The wrongly-based (document-relative) url that the SPA router answered with HTML and that was
+// therefore rejected at store time — it never becomes a downloaded asset.
+const BAD_URL = "https://host.example/media/impostor.woff2";
+
+describe("buildFontGraph validity-aware preference (first-insert race)", () => {
+  it("prefers the face whose src resolves to a downloaded file even when it was inserted SECOND", () => {
+    const graph = graphOf([fontEntry(GOOD_URL, "/assets/cloned/fonts/good.woff2")]);
+    // Insertion order mirrors the real race: the mis-based CSSOM face lands first, the correctly
+    // based css-text face second. Only the good url is a downloaded asset.
+    const faces: FontFace[] = [
+      { family: "Gothic", weight: "400", style: "normal", src: `url("${BAD_URL}") format("woff2")` },
+      { family: "Gothic", weight: "400", style: "normal", src: `url("${GOOD_URL}") format("woff2")` },
+    ];
+    const { entries, css } = buildFontGraph(faces, graph, DOC);
+    const gothic = entries.filter((e) => e.family === "Gothic");
+    assert.equal(gothic.length, 1, "deduped to a single face");
+    assert.equal(gothic[0]!.status, "resolved");
+    assert.deepEqual(gothic[0]!.localPaths, ["/assets/cloned/fonts/good.woff2"]);
+    assert.match(css, /good\.woff2/);
+    assert.doesNotMatch(css, /impostor/);
+  });
+
+  it("keeps the FIRST face when neither resolves (fallback, ties hold order)", () => {
+    const graph = graphOf([]); // nothing downloaded
+    const faces: FontFace[] = [
+      { family: "Gothic", weight: "400", style: "normal", src: `url("${BAD_URL}") format("woff2")` },
+      { family: "Gothic", weight: "400", style: "normal", src: `url("${GOOD_URL}") format("woff2")` },
+    ];
+    const { entries } = buildFontGraph(faces, graph, DOC);
+    const gothic = entries.filter((e) => e.family === "Gothic");
+    assert.equal(gothic.length, 1);
+    assert.equal(gothic[0]!.status, "fallback");
+  });
+
+  it("keeps the FIRST resolving face when BOTH resolve (ties hold insertion order)", () => {
+    const alt = "https://host.example/marketing-static/_next/static/media/alt.woff2";
+    const graph = graphOf([
+      fontEntry(GOOD_URL, "/assets/cloned/fonts/good.woff2"),
+      fontEntry(alt, "/assets/cloned/fonts/alt.woff2"),
+    ]);
+    const faces: FontFace[] = [
+      { family: "Gothic", weight: "400", style: "normal", src: `url("${GOOD_URL}") format("woff2")` },
+      { family: "Gothic", weight: "400", style: "normal", src: `url("${alt}") format("woff2")` },
+    ];
+    const { entries } = buildFontGraph(faces, graph, DOC);
+    const gothic = entries.filter((e) => e.family === "Gothic");
+    assert.equal(gothic.length, 1);
+    assert.deepEqual(gothic[0]!.localPaths, ["/assets/cloned/fonts/good.woff2"], "first resolving wins");
+  });
+});
+
+// --- baseHref-driven relative resolution in buildFontGraph ----------------------------------
+
+describe("buildFontGraph resolves a face's relative src against its owning sheet (baseHref)", () => {
+  it("uses baseHref, not the document url, so ../media climbs from the css file", () => {
+    // The sheet lives at /marketing-static/_next/static/css/sheet.css; `../media/x` from THERE is
+    // /marketing-static/_next/static/media/x.woff2, which is what actually downloaded. Resolved
+    // against the document (/page) it would clamp to /marketing-static/_next/static/media only if
+    // the css path were the base — the point of baseHref.
+    const sheetUrl = "https://host.example/marketing-static/_next/static/css/sheet.css";
+    const resolved = "https://host.example/marketing-static/_next/static/media/x.woff2";
+    const graph = graphOf([fontEntry(resolved, "/assets/cloned/fonts/x.woff2")]);
+    const faces: FontFace[] = [
+      { family: "Gothic", weight: "400", style: "normal", src: 'url("../media/x.woff2") format("woff2")', baseHref: sheetUrl },
+    ];
+    const { entries } = buildFontGraph(faces, graph, DOC);
+    assert.equal(entries[0]!.status, "resolved");
+    assert.deepEqual(entries[0]!.localPaths, ["/assets/cloned/fonts/x.woff2"]);
+  });
+
+  it("falls back to the document url when baseHref is absent (inline <style> / out-of-band parse)", () => {
+    // An out-of-band parse bakes the absolute url into src, so document fallback is harmless.
+    const abs = "https://host.example/fonts/y.woff2";
+    const graph = graphOf([fontEntry(abs, "/assets/cloned/fonts/y.woff2")]);
+    const faces: FontFace[] = [
+      { family: "Mono", weight: "400", style: "normal", src: `url("${abs}") format("woff2")` },
+    ];
+    const { entries } = buildFontGraph(faces, graph, DOC);
+    assert.equal(entries[0]!.status, "resolved");
+  });
+});
diff --git a/compiler/test/fontUrlResolution.test.ts b/compiler/test/fontUrlResolution.test.ts
new file mode 100644
index 0000000..a57402a
--- /dev/null
+++ b/compiler/test/fontUrlResolution.test.ts
@@ -0,0 +1,136 @@
+import { describe, it, before, after } from "node:test";
+import assert from "node:assert/strict";
+import { createServer, type Server } from "node:http";
+import { chromium, type Browser, type Page } from "playwright";
+import { collectPage, type PageSnapshot } from "../src/capture/walker.js";
+
+// A relative url() inside a stylesheet must resolve against THAT sheet's url, not the document.
+// These tests serve real CSS files at a NESTED path so `../media/x` climbs differently depending
+// on the base: against the css file it lands under the nested dir, against the page it clamps to
+// the site root. We assert the harvested url (cssUrls) and the face's baseHref carry the sheet
+// base — the exact fix for the "HTML saved as woff2" font-materialization cluster.
+
+// The nested layout mirrors a real bundler output:
+//   /page                                      (document)
+//   /marketing-static/_next/static/css/x.css   (external sheet)
+//   /marketing-static/_next/static/media/f.woff2  ← where ../media/f.woff2 SHOULD resolve
+const CSS_PATH = "/marketing-static/_next/static/css/x.css";
+const EXPECTED_MEDIA = "/marketing-static/_next/static/media/f.woff2";
+// The WRONG (document-relative) resolution the old code produced:
+const WRONG_MEDIA = "/media/f.woff2";
+
+function serveText(body: string, type: string, res: import("node:http").ServerResponse): void {
+  res.writeHead(200, { "content-type": type });
+  res.end(body);
+}
+
+describe("font url() resolution against the owning stylesheet", () => {
+  let browser: Browser;
+  let page: Page;
+  let server: Server;
+  let origin = "";
+
+  before(async () => {
+    server = createServer((req, res) => {
+      const url = (req.url || "/").split("?")[0];
+      if (url === "/page") {
+        return serveText(
+          `<!doctype html><html><head><link rel="stylesheet" href="${CSS_PATH}"></head><body><p>hi</p></body></html>`,
+          "text/html",
+          res,
+        );
+      }
+      if (url === "/import-host") {
+        // A same-origin sheet that @imports the nested sheet; the imported sheet's own url must be
+        // the base for its faces, not the host sheet or the page.
+        return serveText(
+          `<!doctype html><html><head><link rel="stylesheet" href="/top.css"></head><body><p>hi</p></body></html>`,
+          "text/html",
+          res,
+        );
+      }
+      if (url === "/top.css") {
+        return serveText(`@import url("${CSS_PATH}");`, "text/css", res);
+      }
+      if (url === CSS_PATH) {
+        return serveText(
+          `@font-face{font-family:"Gothic";font-style:normal;font-weight:400;` +
+            `src:url("../media/f.woff2") format("woff2");}` +
+            `.hero{background:url("../media/bg.png")}`,
+          "text/css",
+          res,
+        );
+      }
+      res.writeHead(404).end();
+    });
+    await new Promise<void>((r) => server.listen(0, "127.0.0.1", r));
+    const addr = server.address();
+    if (addr && typeof addr === "object") origin = `http://127.0.0.1:${addr.port}`;
+    browser = await chromium.launch();
+    page = await browser.newPage();
+  });
+
+  after(async () => {
+    await browser.close();
+    await new Promise<void>((r) => server.close(() => r()));
+  });
+
+  const snap = async (path: string): Promise<PageSnapshot> => {
+    await page.goto(`${origin}${path}`, { waitUntil: "networkidle" });
+    await page.evaluate("globalThis.__name = globalThis.__name || ((fn) => fn);");
+    return page.evaluate(collectPage) as Promise<PageSnapshot>;
+  };
+
+  it("resolves a font-face src against the external sheet's url, not the document", async () => {
+    const s = await snap("/page");
+    assert.ok(
+      s.cssUrls.includes(`${origin}${EXPECTED_MEDIA}`),
+      `expected sheet-relative ${EXPECTED_MEDIA} in cssUrls, got ${JSON.stringify(s.cssUrls)}`,
+    );
+    assert.ok(
+      !s.cssUrls.includes(`${origin}${WRONG_MEDIA}`),
+      "must NOT produce the document-relative (wrong) resolution",
+    );
+    const face = s.fontFaces.find((f) => f.family === "Gothic");
+    assert.ok(face, "font face captured");
+    assert.equal(face!.baseHref, `${origin}${CSS_PATH}`, "face carries its owning sheet's base");
+  });
+
+  it("resolves ordinary style-rule url() against the sheet too", async () => {
+    const s = await snap("/page");
+    assert.ok(
+      s.cssUrls.includes(`${origin}/marketing-static/_next/static/media/bg.png`),
+      `expected sheet-relative bg.png, got ${JSON.stringify(s.cssUrls)}`,
+    );
+  });
+
+  it("resolves an @import-nested sheet's face against the IMPORTED sheet's url", async () => {
+    const s = await snap("/import-host");
+    // top.css @imports x.css; the face lives in x.css, so ../media resolves from x.css's dir.
+    assert.ok(
+      s.cssUrls.includes(`${origin}${EXPECTED_MEDIA}`),
+      `@import base must be the imported sheet, got ${JSON.stringify(s.cssUrls)}`,
+    );
+    const face = s.fontFaces.find((f) => f.family === "Gothic");
+    assert.equal(face?.baseHref, `${origin}${CSS_PATH}`);
+  });
+
+  it("falls back to the document base for an inline <style> (no sheet href)", async () => {
+    await page.goto(`${origin}/page`, { waitUntil: "networkidle" });
+    await page.evaluate("globalThis.__name = globalThis.__name || ((fn) => fn);");
+    await page.evaluate(() => {
+      const st = document.createElement("style");
+      st.textContent =
+        '@font-face{font-family:"Inline";src:url("./inline/g.woff2") format("woff2")}';
+      document.head.appendChild(st);
+    });
+    const s = (await page.evaluate(collectPage)) as PageSnapshot;
+    // document base is /page → ./inline/g.woff2 resolves to /inline/g.woff2 (page-relative).
+    assert.ok(
+      s.cssUrls.includes(`${origin}/inline/g.woff2`),
+      `inline <style> resolves against the document, got ${JSON.stringify(s.cssUrls)}`,
+    );
+    const face = s.fontFaces.find((f) => f.family === "Inline");
+    assert.equal(face?.baseHref, undefined, "inline face has no sheet href");
+  });
+});
diff --git a/compiler/test/gates.test.ts b/compiler/test/gates.test.ts
new file mode 100644
index 0000000..616b844
--- /dev/null
+++ b/compiler/test/gates.test.ts
@@ -0,0 +1,188 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { mkdtempSync, mkdirSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { letterSpacingEquivalent, normHref, countVisibleInCaptureHiddenInClone, gate2Assets } from "../src/validate/gates.js";
+import { servedAssetExists } from "../src/validate/validate.js";
+import type { AssetGraph } from "../src/infer/assets.js";
+import type { FontGraph } from "../src/infer/fonts.js";
+import type { IR, IRNode } from "../src/normalize/ir.js";
+import type { PageSnapshot } from "../src/capture/walker.js";
+
+// FIX 5 — the link gate must not fail a javascript: source href against the clone's sanitized value.
+// Generation emits an inert `#` for a `javascript:*` href (React blocks the literal), so normHref
+// collapses every javascript: href — on either side — to `#`, letting the two sides match.
+describe("normHref collapses javascript: hrefs to # (FIX 5)", () => {
+  const origin = "https://example.test";
+  it("normalizes a javascript: source href to #", () => {
+    assert.equal(normHref("Javascript:{}", origin), "#");
+    assert.equal(normHref("javascript:void(0)", origin), "#");
+  });
+  it("makes a javascript: source match the emitted # value", () => {
+    assert.equal(normHref("javascript:{}", origin), normHref("#", origin), "source and clone agree");
+  });
+  it("still distinguishes a real fragment from a full URL", () => {
+    assert.equal(normHref("#top", origin), "#top");
+    assert.equal(normHref("https://example.test/x/", origin), "https://example.test/x");
+  });
+});
+
+// Chromium serializes a computed `letter-spacing: 0` back as the keyword `normal`. The emitter, after
+// snapping a sub-0.1px authored tracking to 0, ships `letter-spacing: 0px` — which the CLONE then
+// reports as `normal` too, but a source that authored an explicit near-zero px can land on either
+// spelling. Gate 4 must treat `normal` and `0px` as equal, or every such node fails on spelling alone.
+describe("gate4 letterSpacing normal ↔ 0px normalization", () => {
+  it("treats `normal` and `0px` as equivalent", () => {
+    assert.ok(letterSpacingEquivalent("normal", "0px"));
+    assert.ok(letterSpacingEquivalent("0px", "normal"));
+  });
+
+  it("treats `normal` and `normal` as equivalent", () => {
+    assert.ok(letterSpacingEquivalent("normal", "normal"));
+  });
+
+  it("treats a sub-2px authored tracking vs `normal` as equivalent (within ±2px)", () => {
+    // source computed `-0.08px`, clone serialized `normal` — a 0.08px delta, well within tolerance.
+    assert.ok(letterSpacingEquivalent("-0.08px", "normal"));
+    assert.ok(letterSpacingEquivalent("normal", "-0.0375px"));
+  });
+
+  it("still equates two close real px values (−0.24px vs −0.2px)", () => {
+    assert.ok(letterSpacingEquivalent("-0.24px", "-0.2px"));
+  });
+
+  it("still FAILS a genuine tracking difference beyond ±2px", () => {
+    assert.ok(!letterSpacingEquivalent("4px", "normal"));
+    assert.ok(!letterSpacingEquivalent("normal", "-3px"));
+    assert.ok(!letterSpacingEquivalent("6px", "2px"));
+  });
+
+  it("passes when the source did not constrain the property (undefined)", () => {
+    assert.ok(letterSpacingEquivalent(undefined, "0px"));
+  });
+});
+
+// A capture-visible text node that the clone renders hidden (off-screen-shifted / banded /
+// width-frozen subtree) is the emil-banner / maxbo-feed regression class. The diagnostic counts
+// DISTINCT source cids whose gen counterpart exists but reports visible:false. Non-blocking; it
+// only has to be a faithful, deterministic count.
+describe("countVisibleInCaptureHiddenInClone diagnostic", () => {
+  // Minimal IR text leaf: `text` at every listed vp, visible per `vis`.
+  const leaf = (id: string, text: string, vis: Record<number, boolean>): IRNode => {
+    const vps = Object.keys(vis).map(Number);
+    const rec = <T,>(v: T): Record<number, T> => Object.fromEntries(vps.map((vp) => [vp, v]));
+    return {
+      id, tag: "a", attrs: {},
+      visibleByVp: vis,
+      bboxByVp: rec({ x: 0, y: 0, width: 100, height: 16 }),
+      computedByVp: rec({} as Record<string, string>),
+      children: [{ text }],
+    } as unknown as IRNode;
+  };
+  const makeIR = (leaves: IRNode[]): IR => ({
+    doc: {} as IR["doc"],
+    root: { id: "n0", tag: "body", attrs: {}, visibleByVp: {}, bboxByVp: {}, computedByVp: {}, children: leaves } as unknown as IRNode,
+  });
+  // Minimal clone snapshot: one node per (cid, visible) with matching direct text.
+  const snap = (nodes: Array<{ cid: string; text: string; visible: boolean }>): PageSnapshot => ({
+    root: {
+      tag: "body", attrs: { "data-cid": "n0" }, computed: {}, bbox: { x: 0, y: 0, width: 100, height: 100 }, visible: true,
+      children: nodes.map((n) => ({
+        tag: "a", attrs: { "data-cid": n.cid }, computed: {}, bbox: { x: 0, y: 0, width: 100, height: 16 },
+        visible: n.visible, children: [{ text: n.text }],
+      })),
+    },
+  } as unknown as PageSnapshot);
+
+  it("counts a source-visible text node the clone renders hidden", () => {
+    const ir = makeIR([leaf("n4", "Enrollment open!", { 375: true })]);
+    const gen = { 375: snap([{ cid: "n4", text: "Enrollment open!", visible: false }]) };
+    assert.equal(countVisibleInCaptureHiddenInClone(ir, gen, [375]), 1);
+  });
+
+  it("does NOT count a node visible in both source and clone", () => {
+    const ir = makeIR([leaf("n4", "Enrollment open!", { 375: true })]);
+    const gen = { 375: snap([{ cid: "n4", text: "Enrollment open!", visible: true }]) };
+    assert.equal(countVisibleInCaptureHiddenInClone(ir, gen, [375]), 0);
+  });
+
+  it("does NOT count a node the SOURCE itself hid (faithful hide)", () => {
+    // maxbo n192 @375: source already off-screen (visible:false) — the clone hiding it is correct.
+    const ir = makeIR([leaf("n192", "Avatar: Fire and Ash", { 375: false, 768: true })]);
+    const gen = {
+      375: snap([{ cid: "n192", text: "Avatar: Fire and Ash", visible: false }]),
+      768: snap([{ cid: "n192", text: "Avatar: Fire and Ash", visible: true }]),
+    };
+    assert.equal(countVisibleInCaptureHiddenInClone(ir, gen, [375, 768]), 0);
+  });
+
+  it("counts a node once even when hidden at several viewports (distinct cids)", () => {
+    const ir = makeIR([leaf("n4", "Enrollment open!", { 375: true, 768: true })]);
+    const gen = {
+      375: snap([{ cid: "n4", text: "Enrollment open!", visible: false }]),
+      768: snap([{ cid: "n4", text: "Enrollment open!", visible: false }]),
+    };
+    assert.equal(countVisibleInCaptureHiddenInClone(ir, gen, [375, 768]), 1);
+  });
+
+  it("ignores whitespace-only text nodes", () => {
+    const ir = makeIR([leaf("n5", "   ", { 375: true })]);
+    const gen = { 375: snap([{ cid: "n5", text: "   ", visible: false }]) };
+    assert.equal(countVisibleInCaptureHiddenInClone(ir, gen, [375]), 0);
+  });
+
+  it("does not count when the clone has no node for the cid (a different miss)", () => {
+    const ir = makeIR([leaf("n4", "Enrollment open!", { 375: true })]);
+    const gen = { 375: snap([]) };
+    assert.equal(countVisibleInCaptureHiddenInClone(ir, gen, [375]), 0);
+  });
+});
+
+// FIX 3 — an aborted srcset-candidate image fetch (requestfailed, file present on disk) must not be
+// counted as a "404" asset failure. servedAssetExists maps a failed URL to a file under the served
+// export exactly as serveStatic does; the assetFailed filter in validate.ts uses it to excuse
+// aborted fetches whose file exists, while genuine misses (>= 400, or file absent) still fail.
+describe("servedAssetExists (FIX 3 aborted-image excuse)", () => {
+  const root = mkdtempSync(join(tmpdir(), "served-out-"));
+  mkdirSync(join(root, "assets", "cloned", "images"), { recursive: true });
+  writeFileSync(join(root, "assets", "cloned", "images", "present.webp"), "RIFFxxxxWEBP");
+
+  it("resolves a URL to a present file under the served root", () => {
+    assert.equal(servedAssetExists(root, "http://127.0.0.1:5000/assets/cloned/images/present.webp"), true);
+  });
+
+  it("returns false when the file is absent from the served root (a genuine miss)", () => {
+    assert.equal(servedAssetExists(root, "http://127.0.0.1:5000/assets/cloned/images/absent.webp"), false);
+  });
+
+  it("ignores query strings when resolving to disk", () => {
+    assert.equal(servedAssetExists(root, "http://127.0.0.1:5000/assets/cloned/images/present.webp?206w"), true);
+  });
+
+  it("does not escape the served root via .. traversal", () => {
+    assert.equal(servedAssetExists(root, "http://127.0.0.1:5000/../../../etc/passwd"), false);
+  });
+
+  it("an unparseable URL is treated as a genuine miss", () => {
+    assert.equal(servedAssetExists(root, "not-a-url"), false);
+  });
+});
+
+describe("gate2Assets failed-asset message (FIX 3)", () => {
+  const emptyAssets: AssetGraph = { entries: [], byUrl: new Map() };
+  const emptyFonts: FontGraph = { entries: [], css: "" };
+
+  it("passes when no generated asset refs are missing", () => {
+    const r = gate2Assets(emptyAssets, emptyFonts, { remoteRefs: [], failed404: [] });
+    assert.equal(r.pass, true);
+    assert.equal(r.metrics.failed404, 0);
+  });
+
+  it("fails and reports missing refs (not '404') when a genuine miss is passed", () => {
+    const r = gate2Assets(emptyAssets, emptyFonts, { remoteRefs: [], failed404: ["failed http://127.0.0.1:5000/assets/cloned/images/absent.webp"] });
+    assert.equal(r.pass, false);
+    assert.equal(r.metrics.failed404, 1);
+    assert.ok(r.issues.some((i) => i.includes("generated asset refs missing")), `expected 'missing' wording, got: ${r.issues.join(" | ")}`);
+  });
+});
diff --git a/compiler/test/htmlBg.test.ts b/compiler/test/htmlBg.test.ts
new file mode 100644
index 0000000..34f64d2
--- /dev/null
+++ b/compiler/test/htmlBg.test.ts
@@ -0,0 +1,44 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { resolveHtmlBg, htmlBgRule } from "../src/generate/app.js";
+
+// Regression: when the source layers a full-bleed backdrop at z-index<0 behind a
+// body-propagated canvas background, emitting an opaque `html { background }`
+// flips CSS 2.1 §14.2 background propagation and buries that backdrop under the
+// body box. `html` must only paint when the SOURCE html actually painted.
+describe("resolveHtmlBg — source-faithful canvas propagation", () => {
+  it("transparent html + colored body → no html background (body propagates to canvas)", () => {
+    const htmlBg = resolveHtmlBg({ htmlBg: "rgba(0, 0, 0, 0)", bodyBg: "rgb(246, 244, 238)" });
+    assert.equal(htmlBg, null);
+    assert.equal(htmlBgRule(htmlBg), "");
+  });
+
+  it("colored html → html background kept", () => {
+    const htmlBg = resolveHtmlBg({ htmlBg: "rgb(10, 20, 30)", bodyBg: "rgb(246, 244, 238)" });
+    assert.equal(htmlBg, "rgb(10, 20, 30)");
+    assert.equal(htmlBgRule(htmlBg), "html { background: rgb(10, 20, 30); }\n");
+  });
+
+  it("both transparent → #ffffff fallback (never a UA-default canvas)", () => {
+    const htmlBg = resolveHtmlBg({ htmlBg: "rgba(0, 0, 0, 0)", bodyBg: "rgba(0, 0, 0, 0)" });
+    assert.equal(htmlBg, "#ffffff");
+    assert.equal(htmlBgRule(htmlBg), "html { background: #ffffff; }\n");
+  });
+
+  it("missing perViewport entry → #ffffff fallback", () => {
+    const htmlBg = resolveHtmlBg(undefined);
+    assert.equal(htmlBg, "#ffffff");
+  });
+
+  it("undefined html + colored body (only body captured) → no html rule", () => {
+    // Body-only styling is the common case the old fallback existed for; it must
+    // still leave html transparent so the body color reaches the canvas.
+    const htmlBg = resolveHtmlBg({ bodyBg: "rgb(0, 0, 0)" });
+    assert.equal(htmlBg, null);
+  });
+
+  it("deterministic: identical input yields identical output", () => {
+    const pv = { htmlBg: "rgba(0, 0, 0, 0)", bodyBg: "rgb(1, 2, 3)" };
+    assert.equal(resolveHtmlBg(pv), resolveHtmlBg({ ...pv }));
+  });
+});
diff --git a/compiler/test/iframeGraft.test.ts b/compiler/test/iframeGraft.test.ts
index 96cc9e7..dc5cbe2 100644
--- a/compiler/test/iframeGraft.test.ts
+++ b/compiler/test/iframeGraft.test.ts
@@ -72,6 +72,23 @@ describe("planForFrameUrl", () => {
     assert.equal(planForFrameUrl("https://static-forms.klaviyo.com/forms/abc"), "graft");
     assert.equal(planForFrameUrl("http://127.0.0.1:4001/iframe-embed.html"), "graft");
   });
+
+  it("SKIPS full-viewport promo POPUP CREATIVE hosts (Attentive/Recart/Wunderkind overlays)", () => {
+    // These vendor hosts serve a full-viewport interstitial creative — grafting pours the
+    // popup's copy into the DOM/text channel and paints the modal over the real page.
+    assert.equal(planForFrameUrl("https://creatives.attn.tv/creative/12345"), "skip");
+    assert.equal(planForFrameUrl("https://creative.attn.tv/loader/x"), "skip");
+    assert.equal(planForFrameUrl("https://app.recart.com/popup/abc"), "skip");
+    assert.equal(planForFrameUrl("https://tag.wunderkind.co/creative"), "skip");
+    assert.equal(planForFrameUrl("https://api.bounceexchange.com/creative"), "skip");
+  });
+
+  it("STILL grafts INLINE embed hosts even for the same vendors (inline forms are a feature)", () => {
+    // Caution guard: a deliberately-grafted inline signup form must never be caught by the
+    // popup-creative skip list. Inline-form hosts differ from overlay-creative hosts.
+    assert.equal(planForFrameUrl("https://static-forms.klaviyo.com/forms/abc"), "graft");
+    assert.equal(planForFrameUrl("https://manage.kmail-lists.com/subscriptions/subscribe"), "graft");
+  });
 });
 
 describe("graftFrameIntoSnapshot", () => {
@@ -146,6 +163,54 @@ describe("graftFrameIntoSnapshot", () => {
     graftFrameIntoSnapshot(host, { idx: 0, contentX: 40, contentY: 30 }, frame);
     assert.ok(host.keyframes.includes("@keyframes spin { to { transform: rotate(360deg); } }"));
   });
+
+  // A frame's `position: fixed` chrome pins to the FRAME viewport, not the page's. Grafted
+  // as plain DOM, `fixed` would resolve against the main page viewport and escape the
+  // iframe's clip box — the observed regression: a gallery embed's
+  // `fixed inset-0 z-[-1]` dark backdrop painted the whole clone dark. It must be demoted
+  // to `absolute` so the host box contains and clips it.
+  it("demotes frame `position: fixed` to `absolute` so it stays inside the iframe box", () => {
+    const backdrop = raw("div", { class: "backdrop" }, [], {
+      computed: { display: "block", position: "fixed" },
+      bbox: { x: 0, y: 0, width: 320, height: 160 },
+    });
+    const frame = pageSnap(raw("body", {}, [backdrop]), "https://frame.test/embed");
+    const host = mkHost();
+    graftFrameIntoSnapshot(host, { idx: 0, contentX: 40, contentY: 30 }, frame);
+    const wrapper = findFrameNode(host.root, 0)!.children[0] as RawNode;
+    const grafted = wrapper.children[0] as RawNode;
+    assert.equal(grafted.computed.position, "absolute");
+  });
+
+  it("demotes frame `position: sticky` to `relative` (no sticking to the page scroll)", () => {
+    const bar = raw("div", { class: "sticky-bar" }, [], {
+      computed: { display: "block", position: "sticky" },
+      bbox: { x: 0, y: 0, width: 320, height: 40 },
+    });
+    const frame = pageSnap(raw("body", {}, [bar]), "https://frame.test/embed");
+    const host = mkHost();
+    graftFrameIntoSnapshot(host, { idx: 0, contentX: 40, contentY: 30 }, frame);
+    const wrapper = findFrameNode(host.root, 0)!.children[0] as RawNode;
+    const grafted = wrapper.children[0] as RawNode;
+    assert.equal(grafted.computed.position, "relative");
+  });
+
+  it("promotes a `static` host to `relative` so demoted absolutes anchor to the frame box", () => {
+    const host = mkHost(); // iframe host computed.position defaults to "static"
+    graftFrameIntoSnapshot(host, { idx: 0, contentX: 40, contentY: 30 }, mkFrame());
+    assert.equal(findFrameNode(host.root, 0)!.computed.position, "relative");
+  });
+
+  it("leaves an already-positioned host's position untouched", () => {
+    const host = pageSnap(raw("body", {}, [
+      raw("iframe", { "data-ditto-frame": "0", src: "https://frame.test/embed" }, [], {
+        computed: { display: "block", position: "absolute" },
+        bbox: { x: 40, y: 30, width: 320, height: 160 },
+      }),
+    ]));
+    graftFrameIntoSnapshot(host, { idx: 0, contentX: 40, contentY: 30 }, mkFrame());
+    assert.equal(findFrameNode(host.root, 0)!.computed.position, "absolute");
+  });
 });
 
 // ---- Cross-origin integration: capture → snapshot graft → IR → generated tag ----
diff --git a/compiler/test/interactions.test.ts b/compiler/test/interactions.test.ts
new file mode 100644
index 0000000..7d387c9
--- /dev/null
+++ b/compiler/test/interactions.test.ts
@@ -0,0 +1,90 @@
+import { describe, it, before, after } from "node:test";
+import assert from "node:assert/strict";
+import { chromium, type Browser, type Page } from "playwright";
+import { captureInteractions, tagElements, diffStyle } from "../src/capture/interactions.js";
+
+describe("diffStyle", () => {
+  it("returns only the changed keys, with the b-side value", () => {
+    const a = { color: "rgb(0, 0, 0)", opacity: "1", transform: "none" };
+    const b = { color: "rgb(255, 0, 0)", opacity: "1", transform: "scale(1.1)" };
+    assert.deepEqual(diffStyle(a, b), { color: "rgb(255, 0, 0)", transform: "scale(1.1)" });
+  });
+  it("is empty when nothing changed", () => {
+    const a = { color: "rgb(0, 0, 0)", opacity: "1" };
+    assert.deepEqual(diffStyle(a, { ...a }), {});
+  });
+  it("only reports keys present in b (b drives the comparison)", () => {
+    // a resting style that carries an extra key does not fabricate a delta.
+    assert.deepEqual(diffStyle({ color: "red", extra: "x" }, { color: "red" }), {});
+  });
+});
+
+describe("captureInteractions hover capture (occlusion-immune)", () => {
+  let browser: Browser;
+  let page: Page;
+  before(async () => {
+    browser = await chromium.launch();
+    page = await browser.newPage({ viewport: { width: 1280, height: 800 } });
+  });
+  after(async () => {
+    await browser.close();
+  });
+
+  const setup = async (html: string) => {
+    await page.setContent(html);
+    await page.evaluate("globalThis.__name = globalThis.__name || ((fn) => fn);");
+    await tagElements(page);
+  };
+
+  it("captures an authored :hover state even when a transparent full-viewport overlay covers the target", async () => {
+    // Exact regression for the empty-hover-capture bug: a modern builder stack parks a
+    // transparent fixed layer over the whole page. page.hover moves the real cursor to the
+    // link's centre, the point lands on the overlay, and `:hover` never reaches the link — so
+    // pointer-based probing captured ZERO hover states. Forcing the pseudo-class fixes it.
+    await setup(`
+      <style>
+        a.cta { color: rgb(0, 0, 0); background-color: rgb(255, 255, 255); }
+        a.cta:hover { color: rgb(255, 0, 0); background-color: rgb(0, 0, 255); }
+        .overlay { position: fixed; inset: 0; z-index: 9999; background: transparent; }
+      </style>
+      <a class="cta" href="#">Shop now</a>
+      <div class="overlay"></div>`);
+    const cap = await captureInteractions(page, { maxCandidates: 50 });
+    const hoverCaps = Object.keys(cap.hover);
+    assert.ok(hoverCaps.length >= 1, "at least one hover state is captured through the overlay");
+    const delta = cap.hover[hoverCaps[0]!]!;
+    assert.equal(delta.color, "rgb(255, 0, 0)", "hover color change is captured");
+    assert.equal(delta.backgroundColor, "rgb(0, 0, 255)", "hover background change is captured");
+  });
+
+  it("captures :hover on a cursor:pointer element that is not a native interactive", async () => {
+    await setup(`
+      <style>
+        .card { cursor: pointer; border: 2px solid rgb(1, 1, 1); }
+        .card:hover { border-color: rgb(9, 9, 9); }
+      </style>
+      <div class="card" style="width:200px;height:120px;">Card</div>`);
+    const cap = await captureInteractions(page, { maxCandidates: 50 });
+    const found = Object.values(cap.hover).some((d) => d.borderTopColor === "rgb(9, 9, 9)");
+    assert.ok(found, "a cursor:pointer card's authored :hover border change is captured");
+  });
+
+  it("records no hover delta for an element with no authored :hover (self-limiting)", async () => {
+    await setup(`
+      <a class="plain" href="#" style="color:rgb(0,0,0);">No hover</a>`);
+    const cap = await captureInteractions(page, { maxCandidates: 50 });
+    assert.equal(Object.keys(cap.hover).length, 0, "no authored hover -> empty hover map");
+  });
+
+  it("restores the resting state after probing (forced pseudo-state cleared)", async () => {
+    await setup(`
+      <style>
+        a.cta { color: rgb(0, 0, 0); }
+        a.cta:hover { color: rgb(255, 0, 0); }
+      </style>
+      <a class="cta" href="#">Link</a>`);
+    await captureInteractions(page, { maxCandidates: 50 });
+    const resting = await page.evaluate(() => getComputedStyle(document.querySelector("a.cta")!).color);
+    assert.equal(resting, "rgb(0, 0, 0)", "the page is left in its resting (non-hover) state");
+  });
+});
diff --git a/compiler/test/irPrune.test.ts b/compiler/test/irPrune.test.ts
index eaac617..f4f02a0 100644
--- a/compiler/test/irPrune.test.ts
+++ b/compiler/test/irPrune.test.ts
@@ -4,7 +4,7 @@ import { mkdtempSync, mkdirSync, writeFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import type { RawNode, RawChild } from "../src/capture/walker.js";
-import { buildIR, isTextChild, type IRNode } from "../src/normalize/ir.js";
+import { buildIR, isTextChild, neutralizeAnimatedTransforms, type IRNode } from "../src/normalize/ir.js";
 
 const VPS = [375, 1280];
 
@@ -98,3 +98,217 @@ describe("IR prune keeps <source> media candidates", () => {
     assert.equal(findByTag(root, "picture"), null);
   });
 });
+
+describe("IR drops font-metric probe nodes (fix 4)", () => {
+  it("excludes a walker-tagged probe node from the IR, keeping its siblings", () => {
+    const probe: RawNode = {
+      ...raw("div", { class: "font-probe" }, [{ text: "Mgy" }]),
+      probe: true,
+    };
+    const real = raw("h1", { class: "title" }, [{ text: "Heading" }]);
+    const body = raw("body", {}, [real, probe]);
+
+    const root = buildFixtureIR(body);
+
+    const kept = root.children.filter((c) => !isTextChild(c)).map((c) => (c as IRNode).tag);
+    assert.deepEqual(kept, ["h1"], "probe div is dropped, the real heading survives");
+    // Its text must not leak into the tree either.
+    assert.equal(findByTag(root, "div"), null);
+  });
+});
+
+describe("IR drops popup-vendor OVERLAY containers, keeps inline embedded forms", () => {
+  it("drops an email-capture popup overlay container (vendor overlay id) but keeps a real section", () => {
+    const overlay = raw("div", { id: "attentive_overlay" }, [
+      raw("iframe", { id: "attentive_creative", src: "https://creatives.attn.tv/x" }),
+    ]);
+    const real = raw("section", { class: "hero" }, [raw("h1", {}, [{ text: "Real content" }])]);
+    const body = raw("body", {}, [real, overlay]);
+
+    const root = buildFixtureIR(body);
+    const kept = root.children.filter((c) => !isTextChild(c)).map((c) => (c as IRNode).tag);
+    assert.deepEqual(kept, ["section"], "the attentive overlay subtree is dropped");
+    assert.equal(findByTag(root, "iframe"), null, "the popup creative iframe never reaches the IR");
+  });
+
+  it("does NOT drop an INLINE embedded signup form that merely carries a vendor name (feature, not popup)", () => {
+    // A deliberately-grafted inline Klaviyo form: a real, sized form embedded in page content. Its
+    // class names the vendor but is NOT an overlay-container marker, so it must survive.
+    const inlineForm = raw("div", { class: "klaviyo-form klaviyo-form-inline" }, [
+      raw("form", { id: "email-signup" }, [raw("input", { type: "email" })]),
+    ]);
+    const body = raw("body", {}, [inlineForm]);
+
+    const root = buildFixtureIR(body);
+    assert.ok(findByTag(root, "form"), "the inline signup form survives the prune");
+    assert.ok(findByTag(root, "input"), "its input survives too");
+  });
+});
+
+// Defect C (normalize side) — an infinite CSS animation gated to a breakpoint (a Webflow `max-lg`
+// marquee) is `animation:none` at the widths it does not run, but the browser still reports the last
+// FROZEN translateX there. `neutralizeAnimatedTransforms` zeroes the transform at EVERY viewport
+// once a genuine infinite animation is present at some width, so no frozen mid-scroll offset (the
+// base residue or the animated phases) is banded and clips the strip offscreen at rest.
+describe("neutralizeAnimatedTransforms (Defect C)", () => {
+  it("zeroes the transform at every viewport when an infinite animation runs at some width", () => {
+    const byVp = {
+      375: { animationName: "track", animationIterationCount: "infinite", transform: "matrix(1, 0, 0, 1, -284.025, 0)" } as any,
+      768: { animationName: "track", animationIterationCount: "infinite", transform: "matrix(1, 0, 0, 1, -280.982, 0)" } as any,
+      1280: { animationName: "none", animationIterationCount: "1", transform: "matrix(1, 0, 0, 1, -9.94731, 0)" } as any,
+    };
+    neutralizeAnimatedTransforms(byVp as any);
+    assert.equal(byVp[375].transform, "none");
+    assert.equal(byVp[768].transform, "none");
+    assert.equal(byVp[1280].transform, "none", "the non-animated base residue is neutralized too");
+  });
+
+  it("leaves a static transform untouched when NO viewport carries an infinite animation", () => {
+    const byVp = {
+      375: { animationName: "none", animationIterationCount: "1", transform: "matrix(1, 0, 0, 1, -40, 0)" } as any,
+      1280: { animationName: "none", animationIterationCount: "1", transform: "matrix(1, 0, 0, 1, -40, 0)" } as any,
+    };
+    neutralizeAnimatedTransforms(byVp as any);
+    assert.equal(byVp[375].transform, "matrix(1, 0, 0, 1, -40, 0)", "a deliberate static offset is preserved");
+    assert.equal(byVp[1280].transform, "matrix(1, 0, 0, 1, -40, 0)");
+  });
+
+  it("does not fire for a FINITE animation (a one-shot entrance, not a perpetual marquee)", () => {
+    const byVp = {
+      375: { animationName: "slideIn", animationIterationCount: "1", transform: "matrix(1, 0, 0, 1, -100, 0)" } as any,
+      1280: { animationName: "slideIn", animationIterationCount: "1", transform: "matrix(1, 0, 0, 1, -100, 0)" } as any,
+    };
+    neutralizeAnimatedTransforms(byVp as any);
+    assert.equal(byVp[375].transform, "matrix(1, 0, 0, 1, -100, 0)", "finite animations own a settled end state, not a perpetual phase");
+  });
+});
+
+/** A RawNode with an explicit computed style and bbox (same at every viewport). Unlike `raw()` this
+ *  lets a test author invisible-but-laid-out boxes, transforms, margins, and positions directly. */
+function rawS(
+  tag: string,
+  computed: Record<string, string>,
+  bbox: { x: number; y: number; width: number; height: number },
+  children: RawChild[] = [],
+  visible = true,
+  attrs: Record<string, string> = {},
+): RawNode {
+  return { tag, attrs, computed, bbox, visible, children };
+}
+
+// FIX 2 — an in-flow `visibility:hidden` box with a nonzero border box is load-bearing geometry: it
+// reserves the row height its absolutely-positioned siblings paint into. It is invisible (so the plain
+// visibility prune would drop it), but dropping it collapses the column. It must survive as a sized
+// placeholder; a genuinely empty display:none-everywhere box must still prune.
+describe("IR prune keeps sized invisible (visibility:hidden) spacers (FIX 2)", () => {
+  it("keeps an in-flow visibility:hidden ghost column with a nonzero bbox", () => {
+    const ghost = rawS(
+      "div",
+      { display: "flex", position: "static", visibility: "hidden" },
+      { x: 0, y: 0, width: 650, height: 723 },
+      // its children are themselves invisible (they set no visibility:visible) — the box is a spacer
+      [rawS("img", { display: "block", position: "static", visibility: "hidden" }, { x: 0, y: 0, width: 650, height: 240 }, [], false)],
+      false,
+    );
+    // the real content is an absolutely-positioned sibling layered over the ghost's reserved space
+    const painted = rawS("img", { display: "block", position: "absolute", visibility: "visible" }, { x: 0, y: 0, width: 650, height: 723 }, [], true);
+    const column = rawS("div", { display: "block", position: "relative", visibility: "visible" }, { x: 0, y: 0, width: 650, height: 723 }, [ghost, painted], true);
+    const body = raw("body", {}, [column]);
+
+    const root = buildFixtureIR(body);
+    const kept = findByTag(root, "div");
+    assert.ok(kept, "the column survives");
+    // The ghost div (a second nested div) must still be present as a sized placeholder.
+    const divs: IRNode[] = [];
+    const collect = (n: IRNode): void => { if (n.tag === "div") divs.push(n); for (const c of n.children) if (!isTextChild(c)) collect(c as IRNode); };
+    collect(root);
+    // column + ghost = 2 divs (body is not a div)
+    assert.equal(divs.length, 2, "the visibility:hidden ghost column is retained, not pruned");
+    const ghostIR = divs.find((d) => d.computedByVp[1280]?.visibility === "hidden");
+    assert.ok(ghostIR, "the retained ghost carries visibility:hidden");
+    assert.ok(ghostIR!.bboxByVp[1280]!.height > 0, "the ghost keeps its load-bearing height");
+  });
+
+  it("still prunes a display:none-everywhere empty box (no resurrection)", () => {
+    const hidden = rawS("div", { display: "none", position: "static", visibility: "visible" }, { x: 0, y: 0, width: 0, height: 0 }, [], false);
+    const body = raw("body", {}, [rawS("section", { display: "block", position: "static", visibility: "visible" }, { x: 0, y: 0, width: 640, height: 100 }, [hidden], true)]);
+    const root = buildFixtureIR(body);
+    assert.equal(findByTag(root, "div"), null, "a display:none-everywhere box stays pruned");
+  });
+
+  it("does not keep an out-of-flow (absolute) visibility:hidden box as a spacer", () => {
+    // Absolute boxes take no space in flow, so an invisible absolute box is not load-bearing geometry.
+    const absHidden = rawS("div", { display: "block", position: "absolute", visibility: "hidden" }, { x: 0, y: 0, width: 300, height: 300 }, [], false);
+    const body = raw("body", {}, [rawS("section", { display: "block", position: "static", visibility: "visible" }, { x: 0, y: 0, width: 640, height: 100 }, [absHidden], true)]);
+    const root = buildFixtureIR(body);
+    assert.equal(findByTag(root, "div"), null, "an out-of-flow invisible box is not kept as a spacer");
+  });
+});
+
+// FIX 3 — a settled loop carousel parks its track with a baked translateX and prepends invisible clone
+// slides that occupy exactly [translateX, 0]; the first REAL slide paints at x=0. Pruning drops the
+// off-screen clones, but the baked translateX would survive verbatim and push every real slide
+// offscreen-left. Re-anchor the track's translateX by the aggregate outer width of the dropped leading
+// clones so the first kept slide lands at its captured position.
+describe("IR prune re-anchors a translated track after dropping leading clones (FIX 3)", () => {
+  it("re-anchors translateX toward 0 by the dropped leading clone width", () => {
+    // Three off-screen leading loop clones, each 200px wide (translateX = -600 = -(3×200)); two reals.
+    // The clones are OFF-SCREEN (visible:false via the off-screen test), NOT visibility:hidden — so
+    // they prune and the FIX-2 sized-invisible-spacer carve-out (which requires visibility:hidden) does
+    // not resurrect them. This mirrors a real settled Splide loop's leading clones.
+    const clone = (i: number): RawNode =>
+      rawS("li", { display: "block", position: "static", visibility: "visible" }, { x: -600 + i * 200, y: 0, width: 200, height: 100 }, [], false);
+    const real = (i: number): RawNode =>
+      rawS("li", { display: "block", position: "static", visibility: "visible" }, { x: i * 200, y: 0, width: 200, height: 100 }, [{ text: `real${i}` }], true);
+    const track = rawS(
+      "ul",
+      { display: "flex", position: "relative", visibility: "visible", transform: "matrix(1, 0, 0, 1, -600, 0)" },
+      { x: 0, y: 0, width: 1000, height: 100 },
+      [clone(0), clone(1), clone(2), real(0), real(1)],
+      true,
+    );
+    const body = raw("body", {}, [track]);
+    const root = buildFixtureIR(body);
+    const ul = findByTag(root, "ul")!;
+    // The clones are pruned (invisible everywhere), leaving the two real slides.
+    const slides = ul.children.filter((c) => !isTextChild(c));
+    assert.equal(slides.length, 2, "only the real slides survive");
+    // The baked -600 translate is re-anchored to 0 (−600 + 3×200).
+    assert.equal(ul.computedByVp[1280]!.transform, "matrix(1, 0, 0, 1, 0, 0)", "track translateX re-anchored to origin");
+    assert.equal(ul.computedByVp[375]!.transform, "matrix(1, 0, 0, 1, 0, 0)", "re-anchored at every viewport");
+  });
+
+  it("leaves a track untouched when no leading children are dropped", () => {
+    const real = (i: number): RawNode =>
+      rawS("li", { display: "block", position: "static", visibility: "visible" }, { x: i * 200, y: 0, width: 200, height: 100 }, [{ text: `real${i}` }], true);
+    const track = rawS(
+      "ul",
+      { display: "flex", position: "relative", visibility: "visible", transform: "matrix(1, 0, 0, 1, -120, 0)" },
+      { x: 0, y: 0, width: 400, height: 100 },
+      [real(0), real(1)],
+      true,
+    );
+    const body = raw("body", {}, [track]);
+    const root = buildFixtureIR(body);
+    const ul = findByTag(root, "ul")!;
+    assert.equal(ul.computedByVp[1280]!.transform, "matrix(1, 0, 0, 1, -120, 0)", "a track with no dropped leading children keeps its offset");
+  });
+
+  it("does not re-anchor when the dropped leading siblings are out of flow", () => {
+    const absClone = (i: number): RawNode =>
+      rawS("li", { display: "block", position: "absolute", visibility: "hidden" }, { x: -400 + i * 200, y: 0, width: 200, height: 100 }, [], false);
+    const real = (i: number): RawNode =>
+      rawS("li", { display: "block", position: "static", visibility: "visible" }, { x: i * 200, y: 0, width: 200, height: 100 }, [{ text: `real${i}` }], true);
+    const track = rawS(
+      "ul",
+      { display: "flex", position: "relative", visibility: "visible", transform: "matrix(1, 0, 0, 1, -80, 0)" },
+      { x: 0, y: 0, width: 400, height: 100 },
+      [absClone(0), absClone(1), real(0), real(1)],
+      true,
+    );
+    const body = raw("body", {}, [track]);
+    const root = buildFixtureIR(body);
+    const ul = findByTag(root, "ul")!;
+    assert.equal(ul.computedByVp[1280]!.transform, "matrix(1, 0, 0, 1, -80, 0)", "out-of-flow clones don't advance the track, so no re-anchor");
+  });
+});
diff --git a/compiler/test/lottiePlaceholder.test.ts b/compiler/test/lottiePlaceholder.test.ts
new file mode 100644
index 0000000..fafd6ee
--- /dev/null
+++ b/compiler/test/lottiePlaceholder.test.ts
@@ -0,0 +1,118 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { DITTO_LOTTIE_TSX } from "../src/generate/lottie.js";
+import { isIdentityTransform, canonicalizeTransforms } from "../src/normalize/ir.js";
+import type { StyleMap } from "../src/normalize/ir.js";
+
+/**
+ * The DittoLottie runtime must NOT erase the captured placeholder frame before the animation
+ * has successfully loaded — a failed load would otherwise blank the container (erasing hero /
+ * logo / footer media). These are string assertions on the emitted 'use client' template.
+ */
+describe("DittoLottie placeholder retention", () => {
+  it("does not clear the container's innerHTML before mounting", () => {
+    assert.ok(
+      !/el\.innerHTML\s*=\s*""/.test(DITTO_LOTTIE_TSX),
+      "template must not eagerly clear the placeholder via el.innerHTML = \"\"",
+    );
+  });
+
+  it("mounts the live animation into a separate overlay child, not the container itself", () => {
+    assert.match(DITTO_LOTTIE_TSX, /createElement\(["']div["']\)/);
+    assert.match(DITTO_LOTTIE_TSX, /container:\s*mount/);
+  });
+
+  it("only removes the placeholder after a successful load event (DOMLoaded)", () => {
+    // The reveal/swap must be gated behind lottie's ready event, and the placeholder removal
+    // must live inside that gated path (removing original children once mount is ready).
+    assert.match(DITTO_LOTTIE_TSX, /addEventListener\(\s*["']DOMLoaded["']/);
+    assert.match(DITTO_LOTTIE_TSX, /removeChild/);
+    // The removal must reference the ready swap, not run unconditionally at mount time.
+    const revealIdx = DITTO_LOTTIE_TSX.indexOf("DOMLoaded");
+    const clearIdx = DITTO_LOTTIE_TSX.indexOf("removeChild");
+    assert.ok(revealIdx >= 0 && clearIdx >= 0, "both the ready gate and the placeholder removal must be present");
+  });
+
+  it("handles a failed load without leaving a broken mount stacked over the placeholder", () => {
+    assert.match(DITTO_LOTTIE_TSX, /data_failed/);
+  });
+
+  // Sizing: the host box carries the captured per-viewport height; only an absolutely-filled overlay
+  // inherits that definite box. If the reveal reverted the overlay to static flow, the player's svg
+  // (style height:100%) would collapse to auto and inflate to the source aspect (a portrait viewBox
+  // then oversizes far past the captured, letterboxed box). So the overlay must STAY absolute/inset
+  // for its whole life, and the reveal must NOT clear those styles.
+  it("mounts the overlay as an absolute, inset-0 layer", () => {
+    assert.match(DITTO_LOTTIE_TSX, /mount\.style\.position\s*=\s*["']absolute["']/);
+    assert.match(DITTO_LOTTIE_TSX, /mount\.style\.inset\s*=\s*["']0["']/);
+  });
+
+  it("keeps the overlay absolute after the swap (never reverts it to static flow)", () => {
+    // The reveal must not strip the overlay's positioning — a `mount.style.position = ""` (or inset)
+    // un-pins it from the host's captured height and lets the runtime svg inflate by aspect.
+    assert.ok(
+      !/mount\.style\.position\s*=\s*["']["']/.test(DITTO_LOTTIE_TSX),
+      "reveal must not clear mount.style.position (would un-pin the overlay → aspect inflation)",
+    );
+    assert.ok(
+      !/mount\.style\.inset\s*=\s*["']["']/.test(DITTO_LOTTIE_TSX),
+      "reveal must not clear mount.style.inset (would un-pin the overlay → aspect inflation)",
+    );
+  });
+
+  it("marks the host with data-ditto-lottie so emitted CSS can force the runtime svg to fit", () => {
+    assert.match(DITTO_LOTTIE_TSX, /setAttribute\(\s*["']data-ditto-lottie["']/);
+  });
+
+  // The player creates its <svg>/<canvas> at runtime WITHOUT a data-cid, so the DOM/media gate can't
+  // map it back to the captured node. The reveal must forward the discarded placeholder's data-cid
+  // onto the runtime-rendered element (validation-agnostic; no gate special-casing).
+  it("forwards the placeholder's data-cid onto the runtime-rendered svg/canvas before the swap", () => {
+    // reads the placeholder cid, then reassigns it to the rendered svg/canvas inside the mount
+    assert.match(DITTO_LOTTIE_TSX, /getAttribute\(\s*["']data-cid["']\s*\)/);
+    assert.match(DITTO_LOTTIE_TSX, /mount\.querySelector\(\s*["']svg,\s*canvas["']\s*\)/);
+    assert.match(DITTO_LOTTIE_TSX, /setAttribute\(\s*["']data-cid["']\s*,/);
+    // the cid capture must precede its removal so the placeholder is still in the DOM when read
+    const readIdx = DITTO_LOTTIE_TSX.indexOf('getAttribute("data-cid")');
+    const removeIdx = DITTO_LOTTIE_TSX.indexOf("removeChild");
+    assert.ok(readIdx >= 0 && removeIdx >= 0 && readIdx < removeIdx, "must read the placeholder cid before removing it");
+  });
+});
+
+describe("identity-transform canonicalization (isIdentityTransform)", () => {
+  it("treats none and identity matrices as identity", () => {
+    assert.equal(isIdentityTransform("none"), true);
+    assert.equal(isIdentityTransform(undefined), true);
+    assert.equal(isIdentityTransform("matrix(1, 0, 0, 1, 0, 0)"), true);
+    assert.equal(isIdentityTransform("matrix(1,0,0,1,0,0)"), true);
+    assert.equal(
+      isIdentityTransform("matrix3d(1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1)"),
+      true,
+    );
+  });
+
+  it("does NOT treat a real (non-identity) transform as identity", () => {
+    assert.equal(isIdentityTransform("matrix(1, 0, 0, 1, 0, 67.75)"), false);
+    assert.equal(isIdentityTransform("translateY(67.75px)"), false);
+    assert.equal(isIdentityTransform("matrix(0.5, 0, 0, 0.5, 0, 0)"), false);
+    assert.equal(isIdentityTransform("matrix3d(1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 10, 0, 1)"), false);
+  });
+
+  it("rewrites identity values to `none` while leaving a real transform observable at other widths", () => {
+    // The contamination scenario: the base viewport (1280) baked a scroll-linked translateY,
+    // while the other widths report identity (none / identity matrix). After canonicalization
+    // the identity widths read literal `none`, so the generator's per-band delta emits the
+    // explicit reset and the base transform can't cascade across bands.
+    const computedByVp: Record<number, StyleMap> = {
+      375: { transform: "none" } as StyleMap,
+      768: { transform: "matrix(1, 0, 0, 1, 0, 0)" } as StyleMap,
+      1280: { transform: "matrix(1, 0, 0, 1, 0, 67.75)" } as StyleMap, // contaminated base
+      1920: { transform: "none" } as StyleMap,
+    };
+    canonicalizeTransforms(computedByVp);
+    assert.equal(computedByVp[375]!.transform, "none");
+    assert.equal(computedByVp[768]!.transform, "none"); // identity matrix normalized to none
+    assert.equal(computedByVp[1280]!.transform, "matrix(1, 0, 0, 1, 0, 67.75)"); // real transform preserved
+    assert.equal(computedByVp[1920]!.transform, "none");
+  });
+});
diff --git a/compiler/test/marqueeDiscriminator.test.ts b/compiler/test/marqueeDiscriminator.test.ts
new file mode 100644
index 0000000..ee594d9
--- /dev/null
+++ b/compiler/test/marqueeDiscriminator.test.ts
@@ -0,0 +1,104 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import {
+  medianVelocityPxPerSec,
+  classifyVelocitySamples,
+  hasRepeatedChildren,
+} from "../src/capture/motion.js";
+
+// These cover the pure discriminators extracted from detectMarquees' in-browser sampling.
+// The regression they defend: on a scroll-LINKED-easing page, a static logo row is still
+// lerping toward its scroll-target right after scrollIntoView, reading as a constant
+// velocity over ONE short window → four phantom marquees at identical -34px/s. The layered
+// tests below make that classification fail.
+
+describe("medianVelocityPxPerSec", () => {
+  it("converts a steady per-120ms delta to px/s and ignores the wrap-reset outlier", () => {
+    // steady -4px per 120ms ≈ -33px/s; one big +200 wrap jump is an outlier the median drops.
+    const deltas = [-4, -4, 200, -4, -4];
+    assert.equal(medianVelocityPxPerSec(deltas, 120), Math.round((-4 / 120) * 1000));
+  });
+  it("returns 0 for empty deltas or a non-positive cadence", () => {
+    assert.equal(medianVelocityPxPerSec([], 120), 0);
+    assert.equal(medianVelocityPxPerSec([-4, -4], 0), 0);
+  });
+});
+
+describe("classifyVelocitySamples — sustained constant velocity (discriminator 2)", () => {
+  const MS = 120;
+  it("PASSES a real marquee: velocity holds across both windows", () => {
+    const w1 = [-4, -4, -4, -4, -4];
+    const w2 = [-4, -4, -4, -4, -4];
+    const r = classifyVelocitySamples(w1, w2, MS);
+    assert.equal(r.isMarquee, true);
+    assert.equal(r.pxPerSec, medianVelocityPxPerSec(w1, MS));
+  });
+
+  it("REJECTS a scroll-settle lerp: velocity decays sharply in window 2 (the false positive)", () => {
+    // window1 still lerping fast toward scroll-target; window2 nearly settled.
+    const w1 = [-4, -4, -4, -4, -4]; // ≈ -33px/s (the phantom "-34px/s")
+    const w2 = [-0.4, -0.4, -0.4, -0.4, -0.4]; // decayed to ~-3px/s
+    assert.equal(classifyVelocitySamples(w1, w2, MS).isMarquee, false);
+  });
+
+  it("REJECTS when window 2 has fully settled (velocity ~0)", () => {
+    const w1 = [-4, -4, -4, -4, -4];
+    const w2 = [0, 0, 0, 0, 0];
+    assert.equal(classifyVelocitySamples(w1, w2, MS).isMarquee, false);
+  });
+
+  it("REJECTS when the direction reverses between windows", () => {
+    const w1 = [-4, -4, -4, -4, -4];
+    const w2 = [4, 4, 4, 4, 4];
+    assert.equal(classifyVelocitySamples(w1, w2, MS).isMarquee, false);
+  });
+
+  it("REJECTS a static row: no motion in either window", () => {
+    assert.equal(classifyVelocitySamples([0, 0, 0], [0, 0, 0], MS).isMarquee, false);
+  });
+
+  it("PASSES a slightly slower-but-still-moving second window (within tolerance)", () => {
+    // small natural jitter (10% slower) must not disqualify a genuine ticker.
+    const w1 = [-4, -4, -4, -4, -4];
+    const w2 = [-3.6, -3.6, -3.6, -3.6, -3.6];
+    assert.equal(classifyVelocitySamples(w1, w2, MS).isMarquee, true);
+  });
+});
+
+describe("hasRepeatedChildren — genuine duplication (discriminator 4)", () => {
+  it("PASSES two consecutive children with an identical outerHTML hash (a cloned copy)", () => {
+    const hashes = [111, 111, 222]; // first two are a literal duplicate
+    const widths = [80, 80, 120];
+    assert.equal(hasRepeatedChildren(hashes, widths), true);
+  });
+
+  it("PASSES a duplicated content block via the repeated width sequence [A B A B]", () => {
+    // hashes differ (cloned then attribute-tweaked) but geometry repeats: [100,60,100,60].
+    const hashes = [1, 2, 3, 4];
+    const widths = [100, 60, 100, 60];
+    assert.equal(hasRepeatedChildren(hashes, widths), true);
+  });
+
+  it("REJECTS a row of distinct logos: no consecutive repetition (the false-positive shape)", () => {
+    // four DIFFERENT logos — the exact static-logo-row case that produced phantom marquees.
+    const hashes = [10, 20, 30, 40];
+    const widths = [90, 110, 75, 130];
+    assert.equal(hasRepeatedChildren(hashes, widths), false);
+  });
+
+  it("REJECTS fewer than two children", () => {
+    assert.equal(hasRepeatedChildren([5], [50]), false);
+    assert.equal(hasRepeatedChildren([], []), false);
+  });
+
+  it("does NOT treat a run of zero-width nodes as repetition (hash 0 / width 0 guards)", () => {
+    assert.equal(hasRepeatedChildren([0, 0], [0, 0]), false);
+    assert.equal(hasRepeatedChildren([1, 2, 3, 4], [0, 0, 0, 0]), false);
+  });
+
+  it("REJECTS an odd-length width sequence that can't split into halves", () => {
+    const hashes = [1, 2, 3];
+    const widths = [100, 60, 100];
+    assert.equal(hasRepeatedChildren(hashes, widths), false);
+  });
+});
diff --git a/compiler/test/overlayDismiss.test.ts b/compiler/test/overlayDismiss.test.ts
new file mode 100644
index 0000000..3ada0b0
--- /dev/null
+++ b/compiler/test/overlayDismiss.test.ts
@@ -0,0 +1,311 @@
+import { describe, it, before, after } from "node:test";
+import assert from "node:assert/strict";
+import { chromium, type Browser, type Page } from "playwright";
+import { finalizeOverlaysInPage, clickDismissInPage } from "../src/capture/capture.js";
+import { irContentExtent, type IRNode, type BBox, type StyleMap } from "../src/normalize/ir.js";
+import { gatePollution } from "../src/validate/gates.js";
+import type { CaptureResult } from "../src/capture/capture.js";
+import type { IR } from "../src/normalize/ir.js";
+
+// tsx/esbuild wraps serialized page functions with __name()/__defProp; shim so page.evaluate works.
+const ESBUILD_SHIM =
+  "globalThis.__name = globalThis.__name || ((fn) => fn);" +
+  "globalThis.__defProp = globalThis.__defProp || Object.defineProperty;";
+
+const VW = 1280, VH = 800;
+
+// ---------------------------------------------------------------------------
+// finalizeOverlaysInPage — effective-z resolution, overlay-unit grouping,
+// lock-relaxed z gate, shadow-root traversal, loud-failure blocking.
+// ---------------------------------------------------------------------------
+describe("capture: finalizeOverlaysInPage overlay detection", () => {
+  let browser: Browser;
+  before(async () => { browser = await chromium.launch(); });
+  after(async () => { await browser.close(); });
+
+  const newPage = async (html: string): Promise<Page> => {
+    const page = await browser.newPage();
+    await page.setViewportSize({ width: VW, height: VH });
+    await page.addInitScript(ESBUILD_SHIM);
+    await page.setContent(html);
+    await page.evaluate(ESBUILD_SHIM);
+    return page;
+  };
+
+  it("groups a 0-height max-z wrapper + its full-viewport z:auto iframe as ONE overlay and removes both (scroll-locked)", async () => {
+    // Mirrors the Attentive structure: body scroll-locked; a fixed z=INT_MAX wrapper of height 0
+    // whose child is a fixed full-viewport iframe with z-index:auto. Neither passes the naive
+    // per-element area+z gate alone (wrapper: area 0; iframe: z parses to 0).
+    const page = await newPage(`
+      <style>
+        html,body{margin:0}
+        body{position:absolute;top:0;left:0;right:0;height:${VH}px;overflow:hidden}
+        #wrap{position:fixed;top:${VH}px;left:0;width:${VW}px;height:0;z-index:2147483647}
+        #creative{position:fixed;top:0;left:0;width:${VW}px;height:${VH}px;z-index:auto;background:#000}
+      </style>
+      <main>real page content</main>
+      <div id="wrap"><iframe id="creative"></iframe></div>
+    `);
+    const res = await page.evaluate(finalizeOverlaysInPage);
+    assert.equal(res.removed, 1, "the wrapper+iframe unit is removed as one node");
+    assert.ok(res.removedLabels.some((l) => l.includes("wrap")), `removed the max-z wrapper (got ${JSON.stringify(res.removedLabels)})`);
+    const gone = await page.evaluate(() => !document.getElementById("wrap") && !document.getElementById("creative"));
+    assert.ok(gone, "both the wrapper and its inner iframe are gone");
+    await page.close();
+  });
+
+  it("detects a z=50 full-viewport fixed dialog ONLY because the page is scroll-locked (lock relaxes the z>=100 gate)", async () => {
+    const page = await newPage(`
+      <style>
+        html,body{margin:0}
+        body{overflow:hidden}
+        #ccpa{position:fixed;inset:0;width:${VW}px;height:${VH}px;z-index:50;background:rgba(0,0,0,.7)}
+      </style>
+      <main>content</main>
+      <div id="ccpa">California Residents Privacy Rights</div>
+    `);
+    const res = await page.evaluate(finalizeOverlaysInPage);
+    assert.equal(res.removed, 1, "the z=50 dialog is removed on a locked page");
+    await page.close();
+  });
+
+  it("does NOT remove a z=50 full-viewport fixed layer when the page is NOT scroll-locked (z floor preserved)", async () => {
+    const page = await newPage(`
+      <style>
+        html,body{margin:0}
+        #hero{position:fixed;inset:0;width:${VW}px;height:${VH}px;z-index:50;background:#eee}
+      </style>
+      <div id="hero">a legit fixed hero, page scrolls normally</div>
+    `);
+    const res = await page.evaluate(finalizeOverlaysInPage);
+    assert.equal(res.removed, 0, "no removal off a locked page — the z>=100 floor guards legit fixed content");
+    assert.equal(res.blocking, false);
+    await page.close();
+  });
+
+  it("removes a promo popup mounted inside an OPEN shadow root and reports the host label", async () => {
+    const page = await newPage(`
+      <style>html,body{margin:0}body{overflow:hidden}</style>
+      <main>content</main>
+      <div id="recart-popup-root"></div>
+      <script>
+        const host = document.getElementById("recart-popup-root");
+        const root = host.attachShadow({ mode: "open" });
+        const layer = document.createElement("div");
+        layer.style.cssText = "position:fixed;inset:0;width:${VW}px;height:${VH}px;z-index:999;background:rgba(0,0,0,.6)";
+        layer.textContent = "Enjoy 15% off";
+        root.appendChild(layer);
+      </script>
+    `);
+    const res = await page.evaluate(finalizeOverlaysInPage);
+    assert.equal(res.removed, 1, "the shadow-hosting popup element is removed as one unit");
+    const gone = await page.evaluate(() => !document.getElementById("recart-popup-root"));
+    assert.ok(gone, "the shadow host is gone from the light DOM");
+    await page.close();
+  });
+
+  it("reports blocking=true when the scroll-lock persists even with NO overlay detected (loud failure)", async () => {
+    // Body is scroll-locked but there is no fixed full-viewport layer to find (e.g. a closed
+    // shadow root we cannot pierce). A silently-locked capture is polluted → surface it.
+    const page = await newPage(`
+      <style>html,body{margin:0}body{overflow:hidden;position:absolute;height:${VH}px}</style>
+      <main>content</main>
+    `);
+    const res = await page.evaluate(finalizeOverlaysInPage);
+    assert.equal(res.removed, 0);
+    assert.equal(res.blocking, true, "a persistent lock with nothing removable still reports blocking");
+    await page.close();
+  });
+
+  it("reports blocking=false and removes nothing on an ordinary unlocked page", async () => {
+    const page = await newPage(`
+      <style>html,body{margin:0}</style>
+      <header>nav</header><main>lots of content</main><footer>footer</footer>
+    `);
+    const res = await page.evaluate(finalizeOverlaysInPage);
+    assert.equal(res.removed, 0);
+    assert.equal(res.blocking, false);
+    assert.equal(res.overlaysRemaining, 0);
+    await page.close();
+  });
+
+  it("protects real sticky page chrome (header/nav) from removal even when detected", async () => {
+    // A scroll-locked page with a sticky header that happens to be tall — the header is PROTECTED,
+    // and it isn't full-viewport, so it never even qualifies. Assert nothing is stripped.
+    const page = await newPage(`
+      <style>
+        html,body{margin:0}body{overflow:hidden}
+        #masthead{position:sticky;top:0;width:${VW}px;height:80px;z-index:1000;background:#fff}
+      </style>
+      <header id="masthead">site chrome</header>
+      <main>content</main>
+    `);
+    const res = await page.evaluate(finalizeOverlaysInPage);
+    const present = await page.evaluate(() => !!document.getElementById("masthead"));
+    assert.ok(present, "the header survives");
+    await page.close();
+  });
+});
+
+// ---------------------------------------------------------------------------
+// clickDismissInPage — decline/close matchers, shadow-root traversal.
+// ---------------------------------------------------------------------------
+describe("capture: clickDismissInPage matchers", () => {
+  let browser: Browser;
+  before(async () => { browser = await chromium.launch(); });
+  after(async () => { await browser.close(); });
+
+  const run = async (html: string): Promise<string[]> => {
+    const page = await browser.newPage();
+    await page.addInitScript(ESBUILD_SHIM);
+    await page.setContent(html);
+    await page.evaluate(ESBUILD_SHIM);
+    const res = await page.evaluate(clickDismissInPage);
+    await page.close();
+    return res;
+  };
+
+  it("clicks a Decline button inside an overlay container (email-capture opt-out)", async () => {
+    const dismissed = await run(`
+      <div class="signup-overlay" style="position:fixed;inset:0;width:400px;height:400px">
+        <button onclick="window.__declined=true">Decline</button>
+      </div>
+    `);
+    assert.ok(dismissed.includes("text:decline"), `clicked Decline (got ${JSON.stringify(dismissed)})`);
+  });
+
+  it("clicks an aria-label close (×) inside an overlay container when no accept/decline text matches", async () => {
+    const dismissed = await run(`
+      <div id="promo-popup" style="position:fixed;inset:0;width:400px;height:400px">
+        <button aria-label="Close dialog">×</button>
+      </div>
+    `);
+    assert.ok(dismissed.some((d) => d.startsWith("close:")), `clicked the aria close (got ${JSON.stringify(dismissed)})`);
+  });
+
+  it("matches an overlay/ccpa/privacy container id/class (extended container selector)", async () => {
+    const dismissed = await run(`
+      <div id="ccpaPop" style="position:fixed;inset:0;width:400px;height:400px">
+        <button>Accept</button>
+      </div>
+    `);
+    assert.ok(dismissed.includes("text:accept"), `matched the ccpa container (got ${JSON.stringify(dismissed)})`);
+  });
+
+  it("traverses an open shadow root to find the close control", async () => {
+    const page = await browser.newPage();
+    await page.addInitScript(ESBUILD_SHIM);
+    await page.setContent(`<div id="host"></div>`);
+    await page.evaluate(ESBUILD_SHIM);
+    await page.evaluate(() => {
+      const host = document.getElementById("host")!;
+      const root = host.attachShadow({ mode: "open" });
+      root.innerHTML = `<div class="popup-modal" style="position:fixed;inset:0;width:400px;height:400px"><button aria-label="close">×</button></div>`;
+    });
+    const dismissed = await page.evaluate(clickDismissInPage);
+    await page.close();
+    assert.ok(dismissed.some((d) => d.startsWith("close:")), `found the shadow-root close (got ${JSON.stringify(dismissed)})`);
+  });
+
+  it("never clicks an ordinary page button outside any overlay container", async () => {
+    const dismissed = await run(`<main><button>Accept</button><a>Continue</a></main>`);
+    assert.deepEqual(dismissed, [], "no overlay container ⇒ no clicks");
+  });
+});
+
+// ---------------------------------------------------------------------------
+// irContentExtent — pure geometry (unclamp / pollution trigger).
+// ---------------------------------------------------------------------------
+describe("normalize: irContentExtent", () => {
+  const bbox = (x: number, y: number, w: number, h: number): BBox => ({ x, y, width: w, height: h });
+  const style = (over: Partial<StyleMap> = {}): StyleMap => ({ position: "static", ...over } as StyleMap);
+  const node = (over: Partial<IRNode>): IRNode => ({
+    id: "n", tag: "div", attrs: {},
+    visibleByVp: { 1280: true }, bboxByVp: { 1280: bbox(0, 0, 100, 100) },
+    computedByVp: { 1280: style() }, children: [], ...over,
+  });
+
+  it("returns the max in-flow descendant border-box bottom", () => {
+    const root = node({
+      tag: "body",
+      children: [
+        node({ bboxByVp: { 1280: bbox(0, 0, 1280, 800) } }),
+        node({ bboxByVp: { 1280: bbox(0, 800, 1280, 4398) } }), // footer bottom = 5198
+      ],
+    });
+    assert.equal(irContentExtent(root, 1280), 5198);
+  });
+
+  it("excludes out-of-flow (fixed/absolute) and floated boxes", () => {
+    const root = node({
+      tag: "body",
+      children: [
+        node({ bboxByVp: { 1280: bbox(0, 0, 1280, 900) } }),
+        node({ computedByVp: { 1280: style({ position: "fixed" }) }, bboxByVp: { 1280: bbox(0, 0, 1280, 9999) } }),
+        node({ computedByVp: { 1280: style({ float: "left" } as Partial<StyleMap>) }, bboxByVp: { 1280: bbox(0, 0, 1280, 8888) } }),
+      ],
+    });
+    assert.equal(irContentExtent(root, 1280), 900, "fixed + float extents ignored");
+  });
+
+  it("descends into nested in-flow subtrees", () => {
+    const root = node({
+      tag: "body",
+      children: [node({ children: [node({ bboxByVp: { 1280: bbox(0, 0, 500, 3000) } })] })],
+    });
+    assert.equal(irContentExtent(root, 1280), 3000);
+  });
+
+  it("ignores nodes invisible at the queried viewport", () => {
+    const root = node({
+      tag: "body",
+      children: [node({ visibleByVp: { 1280: false }, bboxByVp: { 1280: bbox(0, 0, 100, 5000) } })],
+    });
+    assert.equal(irContentExtent(root, 1280), 0);
+  });
+});
+
+// ---------------------------------------------------------------------------
+// gatePollution — scroll-locked-capture contradiction.
+// ---------------------------------------------------------------------------
+describe("validate: pollution gate scroll-locked contradiction", () => {
+  const bbox = (x: number, y: number, w: number, h: number): BBox => ({ x, y, width: w, height: h });
+  const st = (over: Partial<StyleMap> = {}): StyleMap => ({ position: "static", ...over } as StyleMap);
+  // A body with plenty of text and a footer at y=5198 (content extent ~6.4 viewports @800).
+  const mkIr = (): IR => ({
+    doc: {
+      sourceUrl: "https://x.test", title: "t", lang: "en", charset: "UTF-8", metaViewport: "",
+      viewports: [1280], sampleViewports: [1280], canonicalViewport: 1280,
+      perViewport: { 1280: { scrollHeight: 800, scrollWidth: 1280, htmlBg: "", bodyBg: "", bodyColor: "", bodyFont: "" } },
+      nodeCount: 200, keyframes: [],
+    },
+    root: {
+      id: "n0", tag: "body", attrs: {}, visibleByVp: { 1280: true },
+      bboxByVp: { 1280: bbox(0, 0, 1280, 800) }, computedByVp: { 1280: st() },
+      children: [
+        { id: "n1", tag: "section", attrs: {}, visibleByVp: { 1280: true }, bboxByVp: { 1280: bbox(0, 0, 1280, 800) }, computedByVp: { 1280: st() },
+          children: [{ text: "hero copy ".repeat(20) }] },
+        { id: "n2", tag: "footer", attrs: {}, visibleByVp: { 1280: true }, bboxByVp: { 1280: bbox(0, 4074, 1280, 1124) }, computedByVp: { 1280: st() },
+          children: [{ text: "footer copy ".repeat(20) }] },
+      ],
+    },
+  });
+  const mkCapture = (scrollHeight: number): CaptureResult => ({
+    perViewport: [
+      { viewport: 375, height: 812, scrollHeight: 812, nodeCount: 200, truncated: false },
+      { viewport: 1280, height: 800, scrollHeight, nodeCount: 200, truncated: false },
+    ],
+    dismissal: { dismissed: [], overlaysRemaining: 0, removed: 0, videoStills: 0, blocking: false },
+  } as unknown as CaptureResult);
+
+  it("FAILS when scrollHeight is pinned to ~1 viewport at every width but IR content spans multiple viewports", () => {
+    const res = gatePollution(mkIr(), mkCapture(800), [1280]);
+    assert.equal(res.pass, false, "the scroll-locked contradiction is caught");
+    assert.ok(res.issues.some((i) => i.includes("scroll-locked capture")), `issue reported (got ${JSON.stringify(res.issues)})`);
+  });
+
+  it("PASSES when scrollHeight matches the tall content (a genuinely scrollable page)", () => {
+    const res = gatePollution(mkIr(), mkCapture(5198), [1280]);
+    assert.ok(!res.issues.some((i) => i.includes("scroll-locked capture")), "no false positive when the page really scrolled");
+  });
+});
diff --git a/compiler/test/qualityScore.test.ts b/compiler/test/qualityScore.test.ts
new file mode 100644
index 0000000..13ef61c
--- /dev/null
+++ b/compiler/test/qualityScore.test.ts
@@ -0,0 +1,256 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { mkdtempSync, mkdirSync, writeFileSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import {
+  inlineBlobBytes,
+  filePayload,
+  whitespaceLiterals,
+  subpixelArbitraries,
+  customPropTokens,
+  probeArtifacts,
+  uncleanedListeners,
+  tagHistogram,
+  ariaHiddenFocusables,
+  duplicateHelpers,
+  svgPathDuplication,
+  nearDuplicateComponents,
+  componentNames,
+  toLetter,
+  scoreApp,
+  type SrcFile,
+} from "../src/runner/qualityScore.js";
+
+const srcFile = (rel: string, text: string): SrcFile => ({
+  path: rel, rel, ext: rel.slice(rel.lastIndexOf(".")), text, lines: text.split("\n").length,
+});
+
+// ---------------------------------------------------------------------------
+// Metric extractors
+// ---------------------------------------------------------------------------
+
+describe("inlineBlobBytes", () => {
+  it("counts base64 data-URI payload bytes", () => {
+    const b64 = "A".repeat(500);
+    const text = `const img = "data:image/png;base64,${b64}";`;
+    assert.equal(inlineBlobBytes(text), 500);
+  });
+
+  it("counts a long markup string handed in as a prop", () => {
+    const html = "<div>" + "<span>x</span>".repeat(250) + "</div>";
+    const text = `<Frame html={${JSON.stringify(html)}} />`;
+    assert.ok(inlineBlobBytes(text) > 1000, "flags HTML-as-string blob");
+  });
+
+  it("ignores ordinary short strings", () => {
+    assert.equal(inlineBlobBytes(`const s = "hello world";`), 0);
+  });
+});
+
+describe("filePayload", () => {
+  it("reports a giant single line", () => {
+    const giant = "x".repeat(200_000);
+    const p = filePayload(srcFile("a.tsx", `const a = 1;\nconst b = "${giant}";\n`));
+    assert.ok(p.maxLine >= 200_000, "detects the giant line");
+    assert.ok(p.bytes >= 200_000, "counts the bytes");
+  });
+
+  it("a normal formatted file has a small max line", () => {
+    const p = filePayload(srcFile("a.tsx", "const a = 1;\nconst b = 2;\nexport default a;\n"));
+    assert.ok(p.maxLine < 40, "small max line");
+  });
+});
+
+describe("whitespaceLiterals", () => {
+  it("counts {\" \"} capture-whitespace literals", () => {
+    const text = `<p>Hi{" "}there{" "}world{' '}!</p>`;
+    assert.equal(whitespaceLiterals(text), 3);
+  });
+
+  it("does not flag meaningful expression literals", () => {
+    assert.equal(whitespaceLiterals(`<p>{name}{count}</p>`), 0);
+  });
+});
+
+describe("subpixelArbitraries", () => {
+  it("flags non-integer px/rem arbitraries but not whole ones", () => {
+    // 713.938px (frozen) + 12.5rem (=200px, whole) → only the first counts.
+    const text = `<div className="w-[713.938px] h-[12.5rem] p-[16px]" />`;
+    assert.equal(subpixelArbitraries(text), 1);
+  });
+});
+
+describe("customPropTokens", () => {
+  it("splits opaque --clr-N / hash tokens from named ones", () => {
+    const css = `:root{ --clr-7:#fff; --c12:#000; --a1b2c3:#111; --brand-primary:#f00; --space-4:1rem; }`;
+    const t = customPropTokens(css);
+    assert.equal(t.total, 5);
+    assert.equal(t.opaque, 3, "clr-7, c12, hash a1b2c3 are opaque; brand-primary/space-4 are named");
+  });
+});
+
+describe("probeArtifacts", () => {
+  it("flags off-screen capture-probe scaffolding", () => {
+    const text = `<span data-probe="1">m</span><i style={{clip: 'rect(0 0 0 0)'}} />`;
+    assert.ok(probeArtifacts(text) >= 2);
+  });
+});
+
+describe("uncleanedListeners", () => {
+  it("counts addEventListener with no cleanup", () => {
+    const text = `el.addEventListener("scroll", fn);\nwin.addEventListener("resize", fn);`;
+    assert.equal(uncleanedListeners(text), 2);
+  });
+
+  it("does not flag when a matching removeEventListener / teardown exists", () => {
+    const text = `useEffect(() => { el.addEventListener("scroll", fn); return () => el.removeEventListener("scroll", fn); });`;
+    assert.equal(uncleanedListeners(text), 0);
+  });
+});
+
+describe("tagHistogram", () => {
+  it("counts opening element tags by name", () => {
+    const h = tagHistogram(`<div><div/><span>x</span><button>b</button></div>`);
+    assert.equal(h["div"], 2);
+    assert.equal(h["span"], 1);
+    assert.equal(h["button"], 1);
+  });
+});
+
+describe("ariaHiddenFocusables", () => {
+  it("flags aria-hidden on a focusable element", () => {
+    const text = `<button aria-hidden="true">x</button><a aria-hidden={true} href="#">y</a>`;
+    assert.equal(ariaHiddenFocusables(text), 2);
+  });
+
+  it("ignores aria-hidden on a decorative div", () => {
+    assert.equal(ariaHiddenFocusables(`<div aria-hidden="true" />`), 0);
+  });
+});
+
+describe("duplicateHelpers", () => {
+  it("counts copy-paste helper bodies (e.g. a repeated cn())", () => {
+    const body = `{ return classes.filter(Boolean).join(" ").replace(/\\s+/g, " ").trim(); }`;
+    const text = `function cn(...classes) ${body}\nfunction cx(...classes) ${body}\nfunction merge(...classes) ${body}`;
+    const d = duplicateHelpers(text);
+    assert.equal(d.defs, 3);
+    assert.equal(d.dups, 2, "two of the three are identical duplicates");
+  });
+
+  it("does not flag distinct helper bodies", () => {
+    const text = `function a(x) { return x + 1111111111; }\nfunction b(x) { return x - 2222222222; }`;
+    assert.equal(duplicateHelpers(text).dups, 0);
+  });
+});
+
+describe("svgPathDuplication", () => {
+  it("counts repeated inline <path d=...> strings", () => {
+    const d = "M10 10 L20 20 L30 30 Z aaaaaaaaaaaaaaaa";
+    const text = `<path d="${d}"/><path d="${d}"/><path d="M1 1 L2 2 different pathhhhhhhh"/>`;
+    const r = svgPathDuplication(text);
+    assert.equal(r.total, 3);
+    assert.equal(r.repeats, 1);
+  });
+});
+
+describe("nearDuplicateComponents", () => {
+  it("counts pairs sharing a tag signature", () => {
+    assert.equal(nearDuplicateComponents(["div:2,span:1", "div:2,span:1", "nav:1"]), 1);
+    assert.equal(nearDuplicateComponents(["a", "a", "a"]), 2);
+  });
+});
+
+describe("componentNames", () => {
+  it("extracts exported + declared component symbols", () => {
+    const text = `export default function HeroSection(){}\nexport function Footer(){}\nconst Navbar = () => {};`;
+    const names = componentNames(text);
+    assert.ok(names.includes("HeroSection"));
+    assert.ok(names.includes("Footer"));
+    assert.ok(names.includes("Navbar"));
+  });
+});
+
+describe("toLetter", () => {
+  it("maps scores to the expected grade bands", () => {
+    assert.equal(toLetter(95), "A");
+    assert.equal(toLetter(82), "B-");
+    assert.equal(toLetter(75), "C");
+    assert.equal(toLetter(67), "D+");
+    assert.equal(toLetter(59), "F");
+  });
+});
+
+// ---------------------------------------------------------------------------
+// scoreApp — end-to-end on synthetic app trees (generic fixture content)
+// ---------------------------------------------------------------------------
+
+function makeTree(files: Record<string, string>): string {
+  const root = mkdtempSync(join(tmpdir(), "qs-"));
+  for (const [rel, text] of Object.entries(files)) {
+    const p = join(root, rel);
+    mkdirSync(p.slice(0, p.lastIndexOf("/")), { recursive: true });
+    writeFileSync(p, text);
+  }
+  return root;
+}
+
+describe("scoreApp — hard cap on catastrophic payload", () => {
+  it("caps a tree containing a multi-megabyte source file into D-range", () => {
+    const giant = "x".repeat(1_200_000); // >1MB single file
+    const root = makeTree({
+      "src/app/page.tsx": `export default function Page(){ return <main><h1>Hi</h1><section><p>ok</p></section></main>; }`,
+      "src/app/svgs/blob.tsx": `export const blob = "${giant}";`,
+    });
+    try {
+      const rep = scoreApp(root);
+      assert.ok(rep.caps.length > 0, "a catastrophe cap is recorded");
+      assert.ok(rep.total <= 68, `grade is capped into D-range, got ${rep.total}`);
+      assert.ok(["D+", "D", "D-", "F"].includes(rep.grade), `grade ${rep.grade} is D-range or below`);
+      assert.ok(rep.categories.payload!.score < rep.categories.payload!.max * 0.5, "payload dimension collapses");
+    } finally { rmSync(root, { recursive: true, force: true }); }
+  });
+});
+
+describe("scoreApp — semantics", () => {
+  it("penalizes a page with no h1 vs one with a single h1", () => {
+    const withH1 = makeTree({
+      "src/app/page.tsx": `export default function Page(){ return <main><h1>Title</h1><section><p>a</p></section><nav><a href="#">x</a></nav></main>; }`,
+    });
+    const noH1 = makeTree({
+      "src/app/page.tsx": `export default function Page(){ return <div><div><div><div><span>a</span></div></div></div></div>; }`,
+    });
+    try {
+      const a = scoreApp(withH1);
+      const b = scoreApp(noH1);
+      assert.ok(a.categories.semantics!.score > b.categories.semantics!.score, "h1 + semantic tags score higher");
+      assert.equal(b.categories.semantics!.metrics.h1, 0);
+    } finally {
+      rmSync(withH1, { recursive: true, force: true });
+      rmSync(noH1, { recursive: true, force: true });
+    }
+  });
+});
+
+describe("scoreApp — decomposition", () => {
+  it("rates a decomposed tree above a single-file monolith of the same markup", () => {
+    const bodyTags = "<div><p>x</p><a href='#'>l</a></div>".repeat(40);
+    const monolith = makeTree({
+      "src/app/page.tsx": `export default function Page(){ return <main><h1>H</h1>${bodyTags}</main>; }`,
+    });
+    const decomposed = makeTree({
+      "src/app/page.tsx": `import Hero from "./sections/hero";\nimport Feature from "./sections/feature";\nexport default function Page(){ return <main><h1>H</h1><Hero/><Feature/></main>; }`,
+      "src/app/sections/hero.tsx": `export function Hero(){ return <section>${"<div><p>x</p></div>".repeat(20)}</section>; }`,
+      "src/app/sections/feature.tsx": `export function Feature(){ return <section>${"<div><a href='#'>l</a></div>".repeat(20)}</section>; }`,
+    });
+    try {
+      const m = scoreApp(monolith);
+      const d = scoreApp(decomposed);
+      assert.ok(d.categories.decomposition!.score > m.categories.decomposition!.score, "decomposed scores higher on decomposition");
+      assert.ok(d.total > m.total, "and grades higher overall");
+    } finally {
+      rmSync(monolith, { recursive: true, force: true });
+      rmSync(decomposed, { recursive: true, force: true });
+    }
+  });
+});
diff --git a/compiler/test/recipeGridGeometry.test.ts b/compiler/test/recipeGridGeometry.test.ts
new file mode 100644
index 0000000..30e935c
--- /dev/null
+++ b/compiler/test/recipeGridGeometry.test.ts
@@ -0,0 +1,193 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import type { IR, IRNode, IRChild, StyleMap, BBox } from "../src/normalize/ir.js";
+import type { RecipeReport, RecipeCandidate, RecipeResponsiveRegime } from "../src/infer/recipes.js";
+import { recipeResponsiveClassCleaner } from "../src/generate/app.js";
+
+// The recipe pass infers a container's column count by grouping item bounding boxes into rows and
+// taking the widest row. When an item spans multiple tracks that under-reports the real track count,
+// so the synthesized column plan must NOT override the authored/computed grid geometry that the
+// Tailwind emitter already baked into the className. These fixtures build a 3-track grid whose main
+// card spans 2 columns (heuristic reports 2 columns) and assert the emitted classes keep 3 tracks
+// and the span.
+
+const VPS = [768, 1280];
+
+function computed(over: StyleMap = {}): StyleMap {
+  return { display: "block", position: "static", visibility: "visible", whiteSpace: "normal", ...over };
+}
+
+function node(id: string, tag: string, byVp: Record<number, StyleMap>, children: IRChild[] = []): IRNode {
+  const computedByVp: Record<number, StyleMap> = {};
+  const bboxByVp: Record<number, BBox> = {};
+  const visibleByVp: Record<number, boolean> = {};
+  for (const vp of VPS) {
+    computedByVp[vp] = { ...computed(), ...(byVp[vp] ?? {}) };
+    bboxByVp[vp] = { x: 0, y: 0, width: vp, height: 100 };
+    visibleByVp[vp] = true;
+  }
+  return { id, tag, attrs: {}, visibleByVp, bboxByVp, computedByVp, children };
+}
+
+function irWith(root: IRNode): IR {
+  return {
+    doc: {
+      sourceUrl: "https://example.test/",
+      title: "Fixture",
+      lang: "en",
+      charset: "UTF-8",
+      metaViewport: "width=device-width, initial-scale=1",
+      viewports: VPS,
+      sampleViewports: VPS,
+      canonicalViewport: 1280,
+      perViewport: Object.fromEntries(VPS.map((vp) => [vp, { scrollHeight: 800, scrollWidth: vp, htmlBg: "rgb(255,255,255)", bodyBg: "rgb(255,255,255)", bodyColor: "rgb(0,0,0)", bodyFont: "Arial" }])),
+      nodeCount: 4,
+      keyframes: [],
+    },
+    root,
+  };
+}
+
+function regime(viewport: number, columns: number, visibleItems: number): RecipeResponsiveRegime {
+  return { viewport, layout: "grid", rootBox: { x: 0, y: 0, width: viewport, height: 400 }, visibleItems, columns, rows: 1 };
+}
+
+function candidate(over: Partial<RecipeCandidate>): RecipeCandidate {
+  return {
+    id: "r0",
+    kind: "product-grid",
+    confidence: 0.89,
+    risk: "low",
+    rootCid: "n0",
+    rootTag: "section",
+    itemParentCid: "n1",
+    componentName: "ProductGridSection",
+    itemCount: 2,
+    repeatedItems: [],
+    responsiveRegimes: [regime(768, 2, 2), regime(1280, 2, 2)],
+    sourceHints: [],
+    signals: [],
+    emissionStatus: "report-only",
+    fallbackReason: "",
+    ...over,
+  };
+}
+
+function report(candidates: RecipeCandidate[]): RecipeReport {
+  return {
+    version: 1,
+    sourceUrl: "https://example.test/",
+    canonicalViewport: 1280,
+    viewports: VPS,
+    sampledViewports: VPS,
+    summary: { totalCandidates: candidates.length, highConfidence: candidates.length, byKind: {}, templateReadyKinds: [] },
+    candidates,
+  };
+}
+
+// A 3-track grid: the main card spans 2 tracks (`grid-column: 1 / 3`) and a photo occupies track 3.
+// The item-count heuristic groups the two items into one row → columns = 2, which disagrees with the
+// computed 3 tracks.
+function spanningGridIr(): IR {
+  const threeTracks = "284px 284px 284px";
+  const card = node("n2", "article", {
+    768: { gridColumnStart: "1", gridColumnEnd: "3" },
+    1280: { gridColumnStart: "1", gridColumnEnd: "3" },
+  });
+  const photo = node("n3", "img", {
+    768: { gridColumnStart: "3", gridColumnEnd: "4" },
+    1280: { gridColumnStart: "3", gridColumnEnd: "4" },
+  });
+  const parent = node("n1", "div", {
+    768: { display: "grid", gridTemplateColumns: threeTracks },
+    1280: { display: "grid", gridTemplateColumns: threeTracks },
+  }, [card, photo]);
+  return irWith(node("n0", "section", {}, [parent]));
+}
+
+describe("recipe grid geometry: computed tracks/spans are ground truth", () => {
+  it("does not override a 3-track grid with a heuristic 2-column plan (span-2 item present)", () => {
+    const ir = spanningGridIr();
+    const c = candidate({ itemParentCid: "n1", repeatedItems: [
+      { cid: "n2", tag: "article", textSample: "", mediaCount: 1, headingCount: 1, bbox: { x: 0, y: 0, width: 568, height: 300 } },
+      { cid: "n3", tag: "img", textSample: "", mediaCount: 1, headingCount: 0, bbox: { x: 584, y: 0, width: 284, height: 300 } },
+    ] });
+    const clean = recipeResponsiveClassCleaner(ir, report([c]), { tailwind: true });
+
+    // The Tailwind emitter has already put the authored 3-track grid on the container className.
+    const containerIn = "grid grid-cols-3 gap-4";
+    const containerOut = clean("n1", containerIn)!.split(/\s+/);
+    assert.ok(containerOut.includes("grid-cols-3"), "authored 3-track grid-cols-3 survives");
+    assert.ok(!containerOut.some((t) => /(?:^|:)grid-cols-2$/.test(t)), "no synthesized grid-cols-2 override");
+    // No responsive column-plan tokens are appended (the plan was rejected as untrustworthy).
+    assert.ok(!containerOut.some((t) => /^(?:md|lg|2xl):grid-cols-/.test(t)), "no responsive grid-cols plan appended");
+
+    // The span-2 item keeps its authored column span (emitter tokens pass through untouched).
+    const itemOut = clean("n2", "col-start-1 col-end-3 flex flex-col")!;
+    assert.equal(itemOut, "col-start-1 col-end-3 flex flex-col", "span-2 item className is unchanged");
+  });
+
+  it("does not override an ASYMMETRIC 2-track sidebar grid with a grid-cols-2 plan", () => {
+    // A sidebar layout: `grid-template-columns: 260px 1020px` (authored `260px 1fr`). The item-count
+    // heuristic sees 2 items in one row → 2 columns, which agrees with the 2 computed tracks by COUNT.
+    // But `grid-cols-2` = two EQUAL 640px tracks, which destroys the 260/1020 geometry. The plan must be
+    // rejected and the authored template kept.
+    const sidebar = node("n2", "aside", {
+      768: { gridColumnStart: "auto", gridColumnEnd: "auto" },
+      1280: { gridColumnStart: "auto", gridColumnEnd: "auto" },
+    });
+    const main = node("n3", "div", {
+      768: { gridColumnStart: "auto", gridColumnEnd: "auto" },
+      1280: { gridColumnStart: "auto", gridColumnEnd: "auto" },
+    });
+    const parent = node("n1", "div", {
+      768: { display: "grid", gridTemplateColumns: "220px 500px" },
+      1280: { display: "grid", gridTemplateColumns: "260px 1020px" },
+    }, [sidebar, main]);
+    const ir = irWith(node("n0", "section", {}, [parent]));
+    const c = candidate({
+      itemParentCid: "n1",
+      itemCount: 2,
+      responsiveRegimes: [regime(768, 2, 2), regime(1280, 2, 2)],
+      repeatedItems: [
+        { cid: "n2", tag: "aside", textSample: "", mediaCount: 0, headingCount: 0, bbox: { x: 0, y: 0, width: 260, height: 300 } },
+        { cid: "n3", tag: "div", textSample: "", mediaCount: 0, headingCount: 1, bbox: { x: 276, y: 0, width: 1020, height: 300 } },
+      ],
+    });
+    const clean = recipeResponsiveClassCleaner(ir, report([c]), { tailwind: true });
+    // The emitter baked the authored asymmetric template as an arbitrary grid-template-columns utility.
+    const containerIn = "grid grid-cols-[260px_1020px] gap-6";
+    const out = clean("n1", containerIn)!.split(/\s+/);
+    assert.ok(out.includes("grid-cols-[260px_1020px]"), `authored asymmetric template must survive, got: ${out.join(" ")}`);
+    assert.ok(!out.some((t) => /(?:^|:)grid-cols-2$/.test(t)), `no equal-halves grid-cols-2 override, got: ${out.join(" ")}`);
+    assert.ok(!out.some((t) => /^(?:md|lg|2xl):grid-cols-/.test(t)), `no responsive grid-cols plan appended, got: ${out.join(" ")}`);
+  });
+
+  it("still re-flows a genuinely uniform grid whose computed tracks match the heuristic", () => {
+    // 2-track grid at 768, 3-track at 1280, no spanning items → heuristic agrees with computed.
+    const item = (id: string): IRNode => node(id, "article", {
+      768: { gridColumnStart: "auto", gridColumnEnd: "auto" },
+      1280: { gridColumnStart: "auto", gridColumnEnd: "auto" },
+    });
+    const parent = node("n1", "div", {
+      768: { display: "grid", gridTemplateColumns: "300px 300px" },
+      1280: { display: "grid", gridTemplateColumns: "284px 284px 284px" },
+    }, [item("n2"), item("n3"), item("n4")]);
+    const ir = irWith(node("n0", "section", {}, [parent]));
+    const c = candidate({
+      itemParentCid: "n1",
+      itemCount: 3,
+      responsiveRegimes: [regime(768, 2, 3), regime(1280, 3, 3)],
+      repeatedItems: [
+        { cid: "n2", tag: "article", textSample: "", mediaCount: 1, headingCount: 1, bbox: { x: 0, y: 0, width: 300, height: 300 } },
+        { cid: "n3", tag: "article", textSample: "", mediaCount: 1, headingCount: 1, bbox: { x: 316, y: 0, width: 300, height: 300 } },
+        { cid: "n4", tag: "article", textSample: "", mediaCount: 1, headingCount: 1, bbox: { x: 0, y: 316, width: 300, height: 300 } },
+      ],
+    });
+    const clean = recipeResponsiveClassCleaner(ir, report([c]), { tailwind: true });
+    const out = clean("n1", "grid grid-cols-2 gap-4")!.split(/\s+/);
+    // Geometry agreed → the responsive plan is applied: base 2 columns, lg:3 at the wider viewport.
+    assert.ok(out.includes("grid-cols-2"), "base column count applied");
+    assert.ok(out.includes("lg:grid-cols-3"), "responsive column bump applied");
+  });
+});
diff --git a/compiler/test/rotatorGuard.test.ts b/compiler/test/rotatorGuard.test.ts
new file mode 100644
index 0000000..eed2b52
--- /dev/null
+++ b/compiler/test/rotatorGuard.test.ts
@@ -0,0 +1,128 @@
+import { describe, it, before, after } from "node:test";
+import assert from "node:assert/strict";
+import { chromium, type Browser, type Page } from "playwright";
+import type { IR, IRNode } from "../src/normalize/ir.js";
+import type { MotionCapture } from "../src/capture/motion.js";
+import { captureMotion } from "../src/capture/motion.js";
+import { buildMotionSpec, DITTO_MOTION_TSX } from "../src/generate/motion.js";
+
+// A rotator cycles the text of a single LEAF word/phrase. A container that bears element
+// children must never be treated as a rotator: the runtime replaces its content on each swap,
+// so classifying a structural panel as a rotator would flatten its whole subtree to one text
+// node. This regression guards all three defense layers against that misclassification.
+
+// ---- Minimal IR factory (only the fields buildMotionSpec reads: id, attrs, children) ----
+function node(id: string, cap: string | null, children: IRNode[] = [], text?: string): IRNode {
+  const kids = text !== undefined ? ([{ text }] as unknown as IRNode[]) : children;
+  return {
+    id,
+    tag: "div",
+    attrs: cap !== null ? { "data-cid-cap": cap } : {},
+    visibleByVp: {},
+    bboxByVp: {},
+    computedByVp: {},
+    children: kids,
+  } as unknown as IRNode;
+}
+
+function ir(root: IRNode): IR {
+  return { doc: { canonicalViewport: 1280 } as unknown as IR["doc"], root };
+}
+
+function motionWith(rotators: MotionCapture["rotators"]): MotionCapture {
+  return { waapi: [], rotators, reveals: [], marquees: [] };
+}
+
+describe("rotator misclassification guard — layer 1 (emission)", () => {
+  it("emits a rotator whose target is a genuine text leaf (no element children)", () => {
+    const tree = ir(node("n0", null, [node("n1", "5", [], "Design")]));
+    const spec = buildMotionSpec(tree, motionWith([{ cap: "5", texts: ["Design", "Build"], intervalMs: 900 }]));
+    assert.equal(spec.rotators.length, 1, "leaf rotator survives emission");
+    assert.equal(spec.rotators[0]!.cid, "n1");
+  });
+
+  it("DROPS a rotator whose target IR node has element children (structural container)", () => {
+    // n1 is capped and was classified as a rotator, but it holds real element rows (n2, n3).
+    const container = node("n1", "5", [
+      node("n2", null, [], "row one"),
+      node("n3", null, [], "row two"),
+    ]);
+    const tree = ir(node("n0", null, [container]));
+    const spec = buildMotionSpec(tree, motionWith([{ cap: "5", texts: ["a", "b"], intervalMs: 240 }]));
+    assert.equal(spec.rotators.length, 0, "element-bearing container is not emitted as a rotator");
+  });
+
+  it("keeps genuine leaf rotators while dropping a sibling container in the same spec", () => {
+    const tree = ir(node("n0", null, [
+      node("n1", "5", [], "Design"), // genuine leaf
+      node("n2", "6", [node("n3", null, [], "row")]), // container → dropped
+    ]));
+    const spec = buildMotionSpec(tree, motionWith([
+      { cap: "5", texts: ["Design", "Build"], intervalMs: 900 },
+      { cap: "6", texts: ["x", "y"], intervalMs: 240 },
+    ]));
+    assert.equal(spec.rotators.length, 1);
+    assert.equal(spec.rotators[0]!.cid, "n1");
+  });
+});
+
+describe("rotator misclassification guard — layer 3 (non-destructive runtime)", () => {
+  it("saves & restores the target's child NODES, never a flattened textContent string", () => {
+    // Save path: the original child nodes are cloned (structure preserved), not read as a string.
+    assert.match(DITTO_MOTION_TSX, /Array\.from\(el\.childNodes\)\.map\(\(n\) => n\.cloneNode\(true\)\)/);
+    // Restore path: rebuild via replaceChildren with cloned nodes — no `textContent = r.original`.
+    assert.match(DITTO_MOTION_TSX, /r\.el\.replaceChildren\(\.\.\.r\.original\.map\(\(n\) => n\.cloneNode\(true\)\)\)/);
+    assert.doesNotMatch(DITTO_MOTION_TSX, /r\.el\.textContent = r\.original/, "no lossy textContent restore remains");
+  });
+
+  it("refuses to install a rotator on an element that has element children at runtime", () => {
+    assert.match(DITTO_MOTION_TSX, /if \(el\.childElementCount > 0\) continue;/);
+  });
+});
+
+describe("rotator misclassification guard — layer 2 (capture leaf guard)", () => {
+  let browser: Browser;
+  let page: Page;
+  before(async () => {
+    browser = await chromium.launch();
+    page = await browser.newPage();
+  });
+  after(async () => {
+    await browser.close();
+  });
+
+  it("does not record an element-bearing container (runtime-injected uncapped rows) as a rotator", async () => {
+    // #panel is capped BEFORE its rows are injected (mirrors cid-cap tagging preceding the site's
+    // late row appends). Its rows are uncapped. #word is a genuine capped leaf cycling text.
+    await page.setContent(`<!doctype html><html><body>
+      <div id="panel" data-cid-cap="10"></div>
+      <span id="word" data-cid-cap="11">Design</span>
+      <script>
+        var glyphs = ["\\u2b22", "\\u2b21"], gi = 0;
+        var panel = document.getElementById("panel"), rows = 0;
+        // Append real (uncapped) element rows over time, and toggle a glyph inside them.
+        setInterval(function () {
+          if (rows < 4) {
+            var r = document.createElement("div");
+            r.className = "row";
+            r.innerHTML = '<span class="g">' + glyphs[gi % 2] + '</span> line ' + rows;
+            panel.appendChild(r); rows++;
+          } else {
+            gi++;
+            var gs = panel.querySelectorAll(".g");
+            for (var k = 0; k < gs.length; k++) gs[k].textContent = glyphs[gi % 2];
+          }
+        }, 120);
+        // #word: a genuine leaf whose text content cycles.
+        var words = ["Design", "Build", "Ship"], wi = 0, w = document.getElementById("word");
+        setInterval(function () { wi = (wi + 1) % words.length; w.textContent = words[wi]; }, 200);
+      </script>
+    </body></html>`);
+    // tsx/esbuild names the evaluated function; provide the helper it references in-page.
+    await page.evaluate("globalThis.__name = globalThis.__name || ((fn) => fn);");
+    const motion = await captureMotion(page, { observeMs: 1600 });
+    const caps = new Set(motion.rotators.map((r) => r.cap));
+    assert.ok(!caps.has("10"), "element-bearing panel is NOT recorded as a rotator");
+    assert.ok(caps.has("11"), "genuine leaf word IS recorded as a rotator");
+  });
+});
diff --git a/compiler/test/sections.test.ts b/compiler/test/sections.test.ts
new file mode 100644
index 0000000..7d230b1
--- /dev/null
+++ b/compiler/test/sections.test.ts
@@ -0,0 +1,238 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { detectSections, detectSectionNodes } from "../src/infer/sections.js";
+import { planSections } from "../src/generate/sectionSplit.js";
+import type { IR, IRNode, IRChild } from "../src/normalize/ir.js";
+
+const CW = 1280;
+
+type Box = { x?: number; y: number; width?: number; height: number };
+
+/** An element node at the canonical viewport (ids assigned later in pre-order). */
+function el(tag: string, box: Box, children: IRChild[] = [], display = "block"): IRNode {
+  return {
+    id: "",
+    tag,
+    attrs: {},
+    visibleByVp: { [CW]: true },
+    bboxByVp: { [CW]: { x: box.x ?? 0, y: box.y, width: box.width ?? CW, height: box.height } },
+    computedByVp: { [CW]: { display } },
+    children,
+  };
+}
+
+function text(t: string): IRChild {
+  return { text: t };
+}
+
+/** Wrap children in a <body> root and assign stable pre-order ids (n0, n1, …). */
+function page(children: IRNode[], pageH: number): IR {
+  const root = el("body", { y: 0, height: pageH }, children);
+  let i = 0;
+  const assign = (n: IRNode): void => {
+    n.id = `n${i++}`;
+    for (const c of n.children) if ((c as IRNode).tag) assign(c as IRNode);
+  };
+  assign(root);
+  return {
+    doc: {
+      sourceUrl: "https://example.test/", title: "Fixture", lang: "en", charset: "UTF-8",
+      metaViewport: "width=device-width, initial-scale=1",
+      viewports: [CW], sampleViewports: [CW], canonicalViewport: CW,
+      perViewport: { [CW]: { scrollHeight: pageH, scrollWidth: CW, htmlBg: "", bodyBg: "", bodyColor: "", bodyFont: "" } },
+      nodeCount: i, keyframes: [],
+    },
+    root,
+  };
+}
+
+/** A content band with a heading (so section naming has honest evidence). Bands get
+ *  `variant` extra paragraphs so adjacent one-off sections differ structurally — the
+ *  repeated-run filter (≥3 identical signatures → component cluster) must not fire. */
+function band(y: number, height: number, heading: string, variant = 0): IRNode {
+  const extras: IRNode[] = [];
+  for (let k = 0; k <= variant % 7; k++) {
+    extras.push(el("p", { y: y + 80 + k * 30, height: 24, x: 120, width: 600 }, [text(`Body copy ${k}`)]));
+  }
+  return el("section", { y, height }, [
+    el("h2", { y: y + 24, height: 40, x: 120, width: 600 }, [text(heading)]),
+    ...extras,
+  ]);
+}
+
+/** navbar(62) + hero(800) + 3 bands + footer(400), flat under body. */
+function sixBandPage(): IR {
+  const nav = el("nav", { y: 0, height: 62 });
+  const hero = el("section", { y: 62, height: 800 }, [
+    el("h1", { y: 120, height: 60, x: 120, width: 900 }, [text("Ship faster with widgets")]),
+  ]);
+  const b1 = band(862, 600, "Trusted by teams", 0);
+  const b2 = band(1462, 700, "Everything you need", 1);
+  const b3 = band(2162, 500, "What customers say", 2);
+  const footer = el("footer", { y: 2662, height: 400 }, [
+    el("a", { y: 2700, height: 20, x: 120, width: 200, }, [text("Privacy")], "inline"),
+  ]);
+  return page([nav, hero, b1, b2, b3, footer], 3062);
+}
+
+/** Same bands, but body > div#root > (nav + main(13 bands) + footer) — the real-site shape. */
+function wrappedPage(bandCount = 13): IR {
+  const nav = el("nav", { y: 0, height: 62 });
+  const bandH = 900;
+  const bands: IRNode[] = [];
+  for (let k = 0; k < bandCount; k++) {
+    bands.push(k === 0
+      ? el("section", { y: 62, height: bandH }, [el("h1", { y: 100, height: 60, x: 120, width: 900 }, [text("Design your future")])])
+      : band(62 + k * bandH, bandH, `Feature area ${k}`, k));
+  }
+  const mainH = bandCount * bandH;
+  const main = el("main", { y: 62, height: mainH }, bands);
+  const footer = el("footer", { y: 62 + mainH, height: 400 });
+  const pageH = 62 + mainH + 400;
+  const wrapper = el("div", { y: 0, height: pageH }, [nav, main, footer]);
+  return page([wrapper], pageH);
+}
+
+describe("section decomposition (recursive descent)", () => {
+  it("splits navbar + hero + 3 bands + footer into 6 sections", () => {
+    const ir = sixBandPage();
+    const sections = detectSections(ir);
+    assert.equal(sections.length, 6);
+    assert.equal(sections[0]!.role, "navbar");
+    assert.equal(sections[1]!.role, "hero");
+    assert.equal(sections[5]!.role, "footer");
+    // the 62px navbar (below the old 64px bar) is still the navbar
+    assert.equal(sections[0]!.bboxByVp[CW]!.height, 62);
+  });
+
+  it("descends body > div > main wrappers to the real bands", () => {
+    const ir = wrappedPage(13);
+    const sections = detectSections(ir);
+    assert.equal(sections.length, 15); // nav + 13 bands + footer
+    assert.equal(sections[0]!.role, "navbar");
+    assert.equal(sections[1]!.role, "hero");
+    assert.equal(sections[14]!.role, "footer");
+    // no wrapper survives as a section
+    const tags = new Set(detectSectionNodes(ir).map((n) => n.tag));
+    assert.ok(!tags.has("main") && !tags.has("body") && !tags.has("div"));
+  });
+
+  it("sections tile the page top-to-bottom without gaps or overlaps", () => {
+    const ir = wrappedPage(13);
+    const boxes = detectSections(ir).map((s) => s.bboxByVp[CW]!).sort((a, b) => a.y - b.y);
+    const pageH = ir.doc.perViewport[CW]!.scrollHeight;
+    let cursor = 0;
+    for (const b of boxes) {
+      assert.ok(Math.abs(b.y - cursor) <= 8, `gap/overlap at y=${b.y} (expected ~${cursor})`);
+      cursor = b.y + b.height;
+    }
+    assert.ok(pageH - cursor <= 8, `uncovered tail: ${pageH - cursor}px`);
+  });
+
+  it("keeps a single-band page as one section (degenerate stays legal)", () => {
+    const inner = el("div", { y: 100, height: 300, x: 320, width: 640 });
+    const only = el("div", { y: 0, height: 800 }, [inner]);
+    const ir = page([only], 800);
+    const sections = detectSections(ir);
+    assert.equal(sections.length, 1);
+  });
+
+  it("does not split side-by-side columns or overlaid layers", () => {
+    // two full-width overlapping layers inside a page-covering wrapper
+    const a = el("div", { y: 100, height: 1900 });
+    const b = el("div", { y: 100, height: 1900 });
+    const wrapper = el("div", { y: 100, height: 1900 }, [a, b]);
+    const nav = el("nav", { y: 0, height: 100 });
+    const ir = page([nav, wrapper], 2000);
+    const sections = detectSections(ir);
+    assert.equal(sections.length, 2); // nav + the wrapper, unsplit
+  });
+
+  it("does not descend when children leave large coverage gaps", () => {
+    // one small band inside a page-covering container: splitting would drop content
+    const lone = band(0, 300, "Only child");
+    const container = el("div", { y: 0, height: 2000 }, [lone]);
+    const ir = page([container], 2000);
+    assert.equal(detectSections(ir).length, 1);
+  });
+
+  it("keeps a 62px fixed div-wrapped navbar as its own band (nav evidence beats the 64px bar)", () => {
+    // real-site shape: hero at y=0, a thin fixed bar (styled div, real <nav> nested
+    // narrow inside) floating over it
+    const navInner = el("nav", { y: 12, height: 62, x: 700, width: 454 });
+    const bar = el("div", { y: 12, height: 62 }, [el("div", { y: 12, height: 62 }, [navInner])]);
+    const hero = el("section", { y: 0, height: 800 }, [
+      el("h1", { y: 200, height: 60, x: 120, width: 900 }, [text("We recruit designers")]),
+    ]);
+    const b1 = band(800, 700, "Our mission", 1);
+    const b2 = band(1500, 900, "Services", 2);
+    const footer = el("footer", { y: 2400, height: 300 });
+    const ir = page([hero, bar, b1, b2, footer], 2700);
+    const sections = detectSections(ir);
+    assert.equal(sections.length, 5);
+    assert.equal(sections[0]!.role, "hero"); // y=0 sorts before the bar at y=12
+    assert.equal(sections[1]!.role, "navbar");
+    const names = [...planSections(ir).roots.values()];
+    assert.ok(names.includes("Navbar"), `expected Navbar in ${names.join(", ")}`);
+  });
+
+  it("is deterministic: same capture, byte-identical sections", () => {
+    const a = JSON.stringify(detectSections(wrappedPage(13)));
+    const b = JSON.stringify(detectSections(wrappedPage(13)));
+    assert.equal(a, b);
+  });
+});
+
+describe("section component planning (emission roots + names)", () => {
+  it("names one component per band: Navbar, HeroSection, content sections, Footer", () => {
+    const ir = sixBandPage();
+    const plan = planSections(ir);
+    const names = [...plan.roots.values()];
+    assert.equal(names.length, 6);
+    assert.equal(names[0], "Navbar");
+    assert.equal(names[1], "HeroSection");
+    assert.equal(names[5], "Footer");
+    assert.ok(names.includes("TrustedByTeamsSection"));
+    assert.ok(names.includes("WhatCustomersSaySection"));
+    assert.equal(new Set(names).size, 6, "names are unique");
+  });
+
+  it("plans a component per band through body > div > main wrappers", () => {
+    const plan = planSections(wrappedPage(13));
+    assert.equal(plan.roots.size, 15);
+    const names = [...plan.roots.values()];
+    assert.equal(names[0], "Navbar");
+    assert.equal(names[1], "HeroSection");
+    assert.equal(names[14], "Footer");
+  });
+
+  it("falls back to evidence names for bands without headings", () => {
+    const nav = el("nav", { y: 0, height: 62 });
+    const hero = el("section", { y: 62, height: 800 }, [
+      el("h1", { y: 120, height: 60, x: 120, width: 900 }, [text("Hello")]),
+    ]);
+    const formBand = el("section", { y: 862, height: 500 }, [
+      el("form", { y: 900, height: 200, x: 320, width: 640 }),
+    ]);
+    const mediaBand = el("section", { y: 1362, height: 500 }, [
+      el("video", { y: 1400, height: 400, x: 160, width: 960 }),
+    ]);
+    const footer = el("footer", { y: 1862, height: 300 });
+    const ir = page([nav, hero, formBand, mediaBand, footer], 2162);
+    const names = [...planSections(ir).roots.values()];
+    assert.ok(names.includes("ContactSection"), `expected ContactSection in ${names.join(", ")}`);
+    assert.ok(names.includes("MediaSection"), `expected MediaSection in ${names.join(", ")}`);
+  });
+
+  it("leaves a page with too few bands unsplit (no monolithic 'hero' misnomer)", () => {
+    const only = el("div", { y: 0, height: 800 }, [el("div", { y: 100, height: 300, x: 320, width: 640 })]);
+    const plan = planSections(page([only], 800));
+    assert.equal(plan.roots.size, 0);
+  });
+
+  it("is deterministic across runs", () => {
+    const a = JSON.stringify([...planSections(wrappedPage(13)).roots.entries()]);
+    const b = JSON.stringify([...planSections(wrappedPage(13)).roots.entries()]);
+    assert.equal(a, b);
+  });
+});
diff --git a/compiler/test/semanticNaming.test.ts b/compiler/test/semanticNaming.test.ts
new file mode 100644
index 0000000..762f839
--- /dev/null
+++ b/compiler/test/semanticNaming.test.ts
@@ -0,0 +1,177 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { buildColorPalette, colorClusterKey } from "../src/infer/semanticTokens.js";
+import { planSections, nameFromSourceToken } from "../src/generate/sectionSplit.js";
+import type { IR, IRNode, IRChild, StyleMap } from "../src/normalize/ir.js";
+
+const CW = 1280;
+
+type Box = { x?: number; y: number; width?: number; height: number };
+function el(tag: string, box: Box, computed: StyleMap, children: IRChild[] = [], attrs: Record<string, string> = {}, srcClass?: string): IRNode {
+  const n: IRNode = {
+    id: "", tag, attrs,
+    visibleByVp: { [CW]: true },
+    bboxByVp: { [CW]: { x: box.x ?? 0, y: box.y, width: box.width ?? CW, height: box.height } },
+    computedByVp: { [CW]: { display: "block", ...computed } },
+    children,
+  };
+  if (srcClass) n.srcClass = srcClass;
+  return n;
+}
+function text(t: string): IRChild { return { text: t }; }
+
+function page(children: IRNode[], pageH: number, body?: { bodyBg?: string; bodyColor?: string }): IR {
+  // The body carries its own bg/fg computed style (as a real capture does), so the palette's
+  // usage histogram actually sees the page background/foreground colours it will name.
+  const root = el("body", { y: 0, height: pageH }, {
+    ...(body?.bodyBg ? { backgroundColor: body.bodyBg } : {}),
+    ...(body?.bodyColor ? { color: body.bodyColor } : {}),
+  }, children);
+  let i = 0;
+  const assign = (n: IRNode): void => { n.id = `n${i++}`; for (const c of n.children) if ((c as IRNode).tag) assign(c as IRNode); };
+  assign(root);
+  return {
+    doc: {
+      sourceUrl: "https://example.test/", title: "Fixture", lang: "en", charset: "UTF-8",
+      metaViewport: "width=device-width, initial-scale=1",
+      viewports: [CW], sampleViewports: [CW], canonicalViewport: CW,
+      perViewport: { [CW]: { scrollHeight: pageH, scrollWidth: CW, htmlBg: "", bodyBg: body?.bodyBg ?? "", bodyColor: body?.bodyColor ?? "", bodyFont: "" } },
+      nodeCount: i, keyframes: [],
+    },
+    root,
+  } as IR;
+}
+
+// ----------------------------------------------------------------------------
+// 1) Semantic role assignment — a fixture IR with known roles must produce the
+//    expected named tokens (deterministically), leftovers only for role-less colours.
+// ----------------------------------------------------------------------------
+describe("semantic color palette: role assignment", () => {
+  // page bg = cream; body text = near-black; a saturated red brand used on buttons/links;
+  // a light-gray surface used as several card backgrounds; a border gray; one odd accent.
+  function siteIr(): IR {
+    const kids: IRNode[] = [];
+    // Body text (near-black) x8
+    for (let k = 0; k < 8; k++) kids.push(el("p", { y: 100 + k * 30, height: 20 }, { color: "rgb(20, 20, 19)" }, [text("copy")]));
+    // Brand red on buttons/links x6 (interactive → --primary)
+    for (let k = 0; k < 6; k++) kids.push(el("a", { y: 400 + k * 30, height: 40 }, { backgroundColor: "rgb(188, 0, 0)", color: "rgb(255,255,255)" }, [text("Buy")]));
+    // Light-gray card surfaces x5 (bg, light, low-sat → --surface)
+    for (let k = 0; k < 5; k++) kids.push(el("div", { y: 800 + k * 60, height: 50 }, { backgroundColor: "rgb(240, 238, 230)" }));
+    // Border gray x4 (border only → --border)
+    for (let k = 0; k < 4; k++) kids.push(el("div", { y: 1200 + k * 30, height: 20 }, { borderTopColor: "rgb(200, 200, 200)", borderTopWidth: "1px" }));
+    return page(kids, 1600, { bodyBg: "rgb(252, 251, 246)", bodyColor: "rgb(20, 20, 19)" });
+  }
+
+  it("names background / foreground / primary / surface / border from usage evidence", () => {
+    const p = buildColorPalette(siteIr());
+    const byName = new Map(p.tokens.map((t) => [t.name, t.value]));
+    assert.equal(byName.get("--background"), "rgb(252, 251, 246)");
+    assert.equal(byName.get("--foreground"), "rgb(20, 20, 19)");
+    assert.equal(byName.get("--primary"), "rgb(188, 0, 0)");
+    assert.equal(byName.get("--surface"), "rgb(240, 238, 230)");
+    assert.equal(byName.get("--border"), "rgb(200, 200, 200)");
+    // Every named token resolves back to itself.
+    assert.equal(p.varForColor("rgb(188, 0, 0)"), "var(--primary)");
+  });
+
+  it("is deterministic: same IR → byte-identical token list", () => {
+    const a = buildColorPalette(siteIr()).css;
+    const b = buildColorPalette(siteIr()).css;
+    assert.equal(a, b);
+  });
+
+  it("resolves oklab/oklch forms of a named colour to the SAME semantic token (±2 sRGB)", () => {
+    // oklch(0.987… 97°) ≈ rgb(252,251,246) — the page background. Reached only via a
+    // gradient/decoration property, it must still map to --background, not a fresh --clr-N.
+    const p = buildColorPalette(page([
+      ...Array.from({ length: 4 }, (_, k) => el("p", { y: 100 + k * 30, height: 20 }, { color: "rgb(20, 20, 19)" }, [text("x")])),
+    ], 400, { bodyBg: "oklch(0.987472 0.00667657 97.3497)", bodyColor: "rgb(20, 20, 19)" }));
+    const bg = p.tokens.find((t) => t.name === "--background");
+    assert.ok(bg, "background named");
+    // The rgb() equivalent within tolerance resolves to --background via the ±2 fallback.
+    assert.equal(p.varForColor("rgb(252, 251, 246)"), "var(--background)");
+  });
+});
+
+// ----------------------------------------------------------------------------
+// 2) colorClusterKey — visually identical literals share a key; distinct colours don't.
+// ----------------------------------------------------------------------------
+describe("colorClusterKey (interner visual dedup)", () => {
+  it("collapses oklab forms that round to the same sRGB", () => {
+    // Both oklab(0.988…) whites → rgb(251,251,251).
+    const a = colorClusterKey("oklab(0.988242 -0.0000812355 0.00000757745)");
+    const b = colorClusterKey("oklab(0.988371 -0.0000803481 0.00000749468)");
+    assert.ok(a);
+    assert.equal(a, b);
+  });
+  it("keeps genuinely different colours on different keys", () => {
+    assert.notEqual(colorClusterKey("rgb(0,0,0)"), colorClusterKey("rgb(255,255,255)"));
+    assert.notEqual(colorClusterKey("rgb(188,0,0)"), colorClusterKey("rgb(0,0,188)"));
+  });
+  it("separates alpha variants", () => {
+    assert.notEqual(colorClusterKey("rgba(0,0,0,0.5)"), colorClusterKey("rgba(0,0,0,0.75)"));
+  });
+  it("returns null for unparseable values (keeps raw-literal keying)", () => {
+    assert.equal(colorClusterKey("var(--x)"), null);
+    assert.equal(colorClusterKey("currentColor"), null);
+  });
+});
+
+// ----------------------------------------------------------------------------
+// 3) Name sanitization — hashy-suffix stripping + generic-word filtering.
+// ----------------------------------------------------------------------------
+describe("nameFromSourceToken (source-id sanitization)", () => {
+  it("strips Shopify template prefix + trailing hash → semantic slug", () => {
+    assert.equal(nameFromSourceToken("shopify-section-template--19797275672650__split_callout_JtTWTt"), "SplitCallout");
+    // `grid` is a generic structural word (dropped); the hash `RbEALJ` is stripped.
+    assert.equal(nameFromSourceToken("shopify-section-template--19797275672650__media_card_grid_RbEALJ"), "MediaCard");
+  });
+  it("strips mixed-case build hashes (JtTWTt / dDMm2q / RbEALJ)", () => {
+    assert.equal(nameFromSourceToken("split_callout_JtTWTt"), "SplitCallout");
+    assert.equal(nameFromSourceToken("hero_hD9krx"), "Hero");
+  });
+  it("drops generic structural words entirely", () => {
+    assert.equal(nameFromSourceToken("g_section_wrap"), "");
+    assert.equal(nameFromSourceToken("section-inner-content"), "");
+    assert.equal(nameFromSourceToken("shopify-section-group-header"), "Header");
+  });
+  it("handles js-* hooks and long numeric ids", () => {
+    assert.equal(nameFromSourceToken("js-media-banner-section"), "MediaBanner");
+    assert.equal(nameFromSourceToken("template--19797275672650"), "");
+  });
+});
+
+// ----------------------------------------------------------------------------
+// 4) planSections — a Shopify-id section beats a heading slug; noisy classes don't.
+// ----------------------------------------------------------------------------
+describe("planSections: source-id naming precedence", () => {
+  it("names a section from its CMS section id (hash stripped) over generic evidence", () => {
+    const nav = el("nav", { y: 0, height: 62 }, {});
+    const hero = el("section", { y: 62, height: 800 }, {}, [el("h1", { y: 120, height: 60, x: 120, width: 900 }, {}, [text("Welcome")])]);
+    // A one-off band with NO heading but a clean Shopify id → SplitCalloutSection.
+    const callout = el("div", { y: 862, height: 600 }, {}, [
+      el("p", { y: 900, height: 40, x: 120, width: 600 }, {}, [text("Some marketing copy here")]),
+    ], { id: "shopify-section-template--19797275672650__split_callout_JtTWTt" }, "shopify-section js-split-callout-section");
+    const b2 = el("section", { y: 1462, height: 500 }, {}, [el("h2", { y: 1500, height: 40, x: 120, width: 600 }, {}, [text("Everything you need today")]), el("p", { y: 1560, height: 24, x: 120, width: 600 }, {}, [text("extra")])]);
+    const b3 = el("section", { y: 1962, height: 500 }, {}, [el("h2", { y: 2000, height: 40, x: 120, width: 600 }, {}, [text("What customers say now")]), el("p", { y: 2060, height: 24, x: 120, width: 600 }, {}, [text("a")]), el("p", { y: 2090, height: 24, x: 120, width: 600 }, {}, [text("b")])]);
+    const footer = el("footer", { y: 2462, height: 400 }, {}, [el("a", { y: 2500, height: 20, x: 120, width: 200 }, {}, [text("Privacy")], {}, undefined)]);
+    const ir = page([nav, hero, callout, b2, b3, footer], 2862);
+    const names = [...planSections(ir).roots.values()];
+    assert.ok(names.includes("SplitCalloutSection"), `expected SplitCalloutSection in ${names.join(", ")}`);
+  });
+
+  it("does NOT mine arbitrary utility classes (falls back to heading slug)", () => {
+    const nav = el("nav", { y: 0, height: 62 }, {});
+    const hero = el("section", { y: 62, height: 800 }, {}, [el("h1", { y: 120, height: 60, x: 120, width: 900 }, {}, [text("Welcome home")])]);
+    // Heading present, but the only source class is a noisy Webflow utility → use the heading.
+    const band = el("section", { y: 862, height: 600 }, {}, [
+      el("h2", { y: 900, height: 40, x: 120, width: 600 }, {}, [text("Latest releases from us")]),
+    ], {}, "g_section_space duraldar-cta_section w-variant-60a7ad7d");
+    const b2 = el("section", { y: 1462, height: 500 }, {}, [el("h2", { y: 1500, height: 40, x: 120, width: 600 }, {}, [text("Everything you need")]), el("p", { y: 1560, height: 24, x: 120, width: 600 }, {}, [text("x")])]);
+    const footer = el("footer", { y: 1962, height: 400 }, {}, [el("a", { y: 2000, height: 20, x: 120, width: 200 }, {}, [text("Privacy")])]);
+    const ir = page([nav, hero, band, b2, footer], 2362);
+    const names = [...planSections(ir).roots.values()];
+    assert.ok(names.some((n) => /^LatestReleases/.test(n)), `expected heading slug, got ${names.join(", ")}`);
+    assert.ok(!names.some((n) => /Duraldar|Space/.test(n)), `must not mine utility classes: ${names.join(", ")}`);
+  });
+});
diff --git a/compiler/test/seo.test.ts b/compiler/test/seo.test.ts
index 3d514a5..579118b 100644
--- a/compiler/test/seo.test.ts
+++ b/compiler/test/seo.test.ts
@@ -195,3 +195,54 @@ describe("generated Next config", () => {
     assert.ok(NEXT_CONFIG.includes("devIndicators: false"));
   });
 });
+
+describe("SEO origin references the clone, not the source domain (fix 6)", () => {
+  it("sitemap.ts / robots.ts resolve against SITE_ORIGIN, not the source origin", () => {
+    const ir = fixtureIr();
+    const report = buildSeoInventory(ir, fixtureAssets(), fixtureCapture());
+    const files = seoRouteFiles(report, [routeSummaryFromIr(ir, "/", "/", ir.doc.sourceUrl)]);
+    const robots = files.find(([p]) => p === "robots.ts")![1];
+    const sitemap = files.find(([p]) => p === "sitemap.ts")![1];
+    for (const body of [robots, sitemap]) {
+      assert.ok(body.includes('import { SITE_ORIGIN } from "../lib/site";'), "imports SITE_ORIGIN");
+      assert.ok(body.includes("SITE_ORIGIN +"), "builds URLs from SITE_ORIGIN");
+      assert.ok(!body.includes("example.test"), "never bakes the source domain");
+    }
+    // sitemap path is relativized off the source origin.
+    assert.ok(sitemap.includes('SITE_ORIGIN + "/seo"') || sitemap.includes('SITE_ORIGIN + "/"'));
+  });
+
+  it("metadata sets metadataBase from SITE_ORIGIN and relativizes the canonical", () => {
+    const ir = fixtureIr();
+    const report = buildSeoInventory(ir, fixtureAssets(), fixtureCapture());
+    const metadata = metadataExport(report);
+    assert.ok(metadata.includes('new URL(SITE_ORIGIN || "http://localhost:3000")'), "metadataBase from SITE_ORIGIN");
+    assert.ok(metadata.includes('"canonical": "/seo"'), "canonical relativized to a path");
+    // The source domain must not survive in canonical (og:image assets are localized elsewhere).
+    assert.ok(!metadata.includes('"canonical": "https://example.test'), "canonical is not absolute to source");
+  });
+
+  it("relativizes og:url off the source origin", () => {
+    const ir = fixtureIr();
+    ir.doc.head!.meta!.push({ property: "og:url", content: "https://example.test/seo" });
+    const report = buildSeoInventory(ir, fixtureAssets(), fixtureCapture());
+    const metadata = metadataExport(report);
+    assert.ok(metadata.includes('"url": "/seo"'), "og:url relativized to a path");
+    assert.ok(!metadata.includes('"url": "https://example.test/seo"'), "og:url not absolute to source");
+  });
+
+  it("rewrites on-origin JSON-LD @id/url off the source domain via SITE_ORIGIN", () => {
+    const ir = fixtureIr();
+    // JSON-LD carrying the source origin in @id/url (escaped-slash form, like WordPress emits).
+    ir.doc.head!.jsonLd = [{
+      id: "graph",
+      text: '{"@context":"https:\\/\\/schema.org","@id":"https:\\/\\/example.test\\/#website","url":"https:\\/\\/example.test\\/"}',
+    }];
+    const report = buildSeoInventory(ir, fixtureAssets(), fixtureCapture());
+    const markup = jsonLdHeadMarkup(report);
+    assert.ok(markup.includes(".join(SITE_ORIGIN)"), "rejoins segments with SITE_ORIGIN at runtime");
+    // The source origin must not survive as a literal (schema.org context is off-origin, kept).
+    assert.ok(!markup.includes("example.test"), "source origin removed from JSON-LD");
+    assert.ok(markup.includes("schema.org"), "off-origin @context left untouched");
+  });
+});
diff --git a/compiler/test/serveRange.test.ts b/compiler/test/serveRange.test.ts
new file mode 100644
index 0000000..c5eb342
--- /dev/null
+++ b/compiler/test/serveRange.test.ts
@@ -0,0 +1,205 @@
+import { describe, it, before, after } from "node:test";
+import assert from "node:assert/strict";
+import { mkdtempSync, rmSync, writeFileSync, mkdirSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { serveStatic, parseRangeHeader, pendingFontFamilies, unreferencedFontFaces, type FontFaceStatus } from "../src/validate/render.js";
+
+// ---- Pure helper: parseRangeHeader ----
+describe("parseRangeHeader", () => {
+  const SIZE = 1000;
+
+  it("no header → full 200", () => {
+    assert.deepEqual(parseRangeHeader(undefined, SIZE), { kind: "full" });
+    assert.deepEqual(parseRangeHeader("", SIZE), { kind: "full" });
+  });
+
+  it("bytes=0- (Chromium's open-ended media probe) → whole file as a range", () => {
+    assert.deepEqual(parseRangeHeader("bytes=0-", SIZE), { kind: "range", start: 0, end: 999 });
+  });
+
+  it("bounded range bytes=100-199 → [100,199] inclusive", () => {
+    assert.deepEqual(parseRangeHeader("bytes=100-199", SIZE), { kind: "range", start: 100, end: 199 });
+  });
+
+  it("end past EOF is clamped to size-1", () => {
+    assert.deepEqual(parseRangeHeader("bytes=900-5000", SIZE), { kind: "range", start: 900, end: 999 });
+  });
+
+  it("suffix range bytes=-100 → last 100 bytes", () => {
+    assert.deepEqual(parseRangeHeader("bytes=-100", SIZE), { kind: "range", start: 900, end: 999 });
+  });
+
+  it("suffix larger than file → whole file", () => {
+    assert.deepEqual(parseRangeHeader("bytes=-5000", SIZE), { kind: "range", start: 0, end: 999 });
+  });
+
+  it("start at or past EOF → unsatisfiable (416)", () => {
+    assert.deepEqual(parseRangeHeader("bytes=1000-", SIZE), { kind: "unsatisfiable" });
+    assert.deepEqual(parseRangeHeader("bytes=2000-3000", SIZE), { kind: "unsatisfiable" });
+  });
+
+  it("zero-length resource → unsatisfiable for any range", () => {
+    assert.deepEqual(parseRangeHeader("bytes=0-", 0), { kind: "unsatisfiable" });
+  });
+
+  it("malformed / multi-range / inverted → full (safe fallback, never throws)", () => {
+    assert.deepEqual(parseRangeHeader("bytes=abc-def", SIZE), { kind: "full" });
+    assert.deepEqual(parseRangeHeader("items=0-10", SIZE), { kind: "full" });
+    assert.deepEqual(parseRangeHeader("bytes=0-10,20-30", SIZE), { kind: "full" }); // multi-range collapsed
+    assert.deepEqual(parseRangeHeader("bytes=-", SIZE), { kind: "full" });
+    assert.deepEqual(parseRangeHeader("bytes=500-100", SIZE), { kind: "full" }); // inverted
+  });
+});
+
+// ---- Pure helper: pendingFontFamilies (the font-load wait decision) ----
+// The render walk must run after webfonts are APPLIED, else text boxes measure the fallback face
+// (a systematic width delta wrongly attributed to the clone). This helper is the state-based (not
+// time-based) predicate the in-page poll ends on: it returns the DECLARED families still actively
+// fetching. Browsers lazy-load faces, so after document.fonts.ready a face the rendered text needs
+// is already "loading"; a face left "unloaded" is unreferenced and will never load on its own —
+// waiting on it only burns the cap, so ONLY "loading" is pending.
+describe("pendingFontFamilies", () => {
+  const face = (family: string, status: string, weight = "400", style = "normal"): FontFaceStatus => ({ family, weight, style, status });
+
+  it("no faces declared → nothing pending", () => {
+    assert.deepEqual(pendingFontFamilies([]), []);
+  });
+
+  it("all faces loaded → nothing pending (walk may proceed)", () => {
+    assert.deepEqual(pendingFontFamilies([face("Avenir", "loaded"), face("Inter", "loaded")]), []);
+  });
+
+  it("an unloaded face is unreferenced (lazy-load) → NOT pending", () => {
+    assert.deepEqual(pendingFontFamilies([face("Avenir", "unloaded")]), []);
+  });
+
+  it("a loading face makes its family pending", () => {
+    assert.deepEqual(pendingFontFamilies([face("Avenir", "loading")]), ["Avenir"]);
+  });
+
+  it("errored faces are terminal — never reported pending (waiting longer is pointless)", () => {
+    assert.deepEqual(pendingFontFamilies([face("Avenir", "error")]), []);
+  });
+
+  it("a family is pending if ANY weight is still loading", () => {
+    const faces = [face("Avenir", "loaded", "400"), face("Avenir", "loading", "700")];
+    assert.deepEqual(pendingFontFamilies(faces), ["Avenir"]);
+  });
+
+  it("a partially-used family (used face loaded, sibling faces unloaded) is NOT pending", () => {
+    // The real-world false positive this fix removes: a matched face loaded, unreferenced
+    // weight/style siblings stay "unloaded" — the walk may proceed without waiting on them.
+    const faces = [face("Avenir", "loaded", "400"), face("Avenir", "unloaded", "700"), face("Avenir", "unloaded", "400", "italic")];
+    assert.deepEqual(pendingFontFamilies(faces), []);
+  });
+
+  it("a family whose faces are all terminal (loaded or errored) is not pending", () => {
+    const faces = [face("Avenir", "loaded", "400"), face("Avenir", "error", "700")];
+    assert.deepEqual(pendingFontFamilies(faces), []);
+  });
+
+  it("strips surrounding quotes from the reported family name and dedupes+sorts (loading only)", () => {
+    const faces = [face('"Source Serif"', "loading"), face("Avenir", "loading"), face("Avenir", "unloaded")];
+    assert.deepEqual(pendingFontFamilies(faces), ["Avenir", "Source Serif"]);
+  });
+
+  it("only the still-loading families are returned when some are loaded/unloaded", () => {
+    const faces = [face("Inter", "loaded"), face("Avenir", "loading"), face("JetBrains", "unloaded")];
+    assert.deepEqual(pendingFontFamilies(faces), ["Avenir"]);
+  });
+});
+
+// ---- Pure helper: unreferencedFontFaces (informational-only per-face report) ----
+// Faces left "unloaded" after the wait bound: declared but no rendered text resolves to them.
+// Reported per-face (family+weight+style) for an informational log; benign, never a fidelity issue.
+describe("unreferencedFontFaces", () => {
+  const face = (family: string, status: string, weight = "400", style = "normal"): FontFaceStatus => ({ family, weight, style, status });
+
+  it("returns only the unloaded faces (not loaded/loading/error)", () => {
+    const faces = [face("Avenir", "loaded"), face("Merriweather", "unloaded", "700"), face("Inter", "loading"), face("Gotham", "error")];
+    assert.deepEqual(unreferencedFontFaces(faces), [{ family: "Merriweather", weight: "700", style: "normal", status: "unloaded" }]);
+  });
+
+  it("reports per-face (family+weight+style), not collapsed per-family, and strips quotes + sorts", () => {
+    const faces = [
+      face('"Merriweather"', "unloaded", "700", "normal"),
+      face("Merriweather", "unloaded", "300", "italic"),
+      face("Avenir", "unloaded", "400", "normal"),
+    ];
+    assert.deepEqual(unreferencedFontFaces(faces), [
+      { family: "Avenir", weight: "400", style: "normal", status: "unloaded" },
+      { family: "Merriweather", weight: "300", style: "italic", status: "unloaded" },
+      { family: "Merriweather", weight: "700", style: "normal", status: "unloaded" },
+    ]);
+  });
+
+  it("no unloaded faces → empty", () => {
+    assert.deepEqual(unreferencedFontFaces([face("Avenir", "loaded"), face("Inter", "loading")]), []);
+  });
+});
+
+// ---- Integration: serveStatic answers real Range requests with 206/416 ----
+describe("serveStatic Range support (integration)", () => {
+  let rootDir = "";
+  let base = "";
+  let close: (() => Promise<void>) | null = null;
+  const BODY = Buffer.alloc(5000, 0x41); // 5000 'A' bytes stands in for a media file
+
+  before(async () => {
+    rootDir = mkdtempSync(join(tmpdir(), "ditto-serve-"));
+    mkdirSync(join(rootDir, "assets"), { recursive: true });
+    writeFileSync(join(rootDir, "assets", "hero.webm"), BODY);
+    writeFileSync(join(rootDir, "index.html"), "<!doctype html><html><body>ok</body></html>");
+    const s = await serveStatic(rootDir);
+    base = s.url;
+    close = s.close;
+  });
+
+  after(async () => {
+    await close?.();
+    rmSync(rootDir, { recursive: true, force: true });
+  });
+
+  it("open-ended Range bytes=0- → 206 with a bounded body + Content-Range/Accept-Ranges", async () => {
+    const res = await fetch(base + "/assets/hero.webm", { headers: { Range: "bytes=0-" } });
+    assert.equal(res.status, 206);
+    assert.equal(res.headers.get("accept-ranges"), "bytes");
+    assert.equal(res.headers.get("content-range"), `bytes 0-4999/5000`);
+    assert.equal(res.headers.get("content-type"), "video/webm");
+    const buf = Buffer.from(await res.arrayBuffer());
+    assert.equal(buf.length, 5000);
+  });
+
+  it("bounded Range bytes=100-199 → 206 returning exactly those 100 bytes", async () => {
+    const res = await fetch(base + "/assets/hero.webm", { headers: { Range: "bytes=100-199" } });
+    assert.equal(res.status, 206);
+    assert.equal(res.headers.get("content-range"), `bytes 100-199/5000`);
+    const buf = Buffer.from(await res.arrayBuffer());
+    assert.equal(buf.length, 100);
+    assert.ok(buf.equals(BODY.subarray(100, 200)));
+  });
+
+  it("Range past EOF → 416 with Content-Range: bytes */size", async () => {
+    const res = await fetch(base + "/assets/hero.webm", { headers: { Range: "bytes=9000-" } });
+    assert.equal(res.status, 416);
+    assert.equal(res.headers.get("content-range"), `bytes */5000`);
+    // Drain the (empty) body so the socket is released.
+    await res.arrayBuffer();
+  });
+
+  it("no Range header → full 200 with Accept-Ranges advertised", async () => {
+    const res = await fetch(base + "/assets/hero.webm");
+    assert.equal(res.status, 200);
+    assert.equal(res.headers.get("accept-ranges"), "bytes");
+    const buf = Buffer.from(await res.arrayBuffer());
+    assert.equal(buf.length, 5000);
+  });
+
+  it("HTML routes still serve a normal 200 (Range logic doesn't disturb pages)", async () => {
+    const res = await fetch(base + "/");
+    assert.equal(res.status, 200);
+    const text = await res.text();
+    assert.match(text, /<body>ok<\/body>/);
+  });
+});
diff --git a/compiler/test/svgRootFill.test.ts b/compiler/test/svgRootFill.test.ts
new file mode 100644
index 0000000..35a8d97
--- /dev/null
+++ b/compiler/test/svgRootFill.test.ts
@@ -0,0 +1,60 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { resolveSvgRootFill, isRealPaint } from "../src/generate/app.js";
+
+describe("isRealPaint", () => {
+  it("treats none / empty / transparent as non-paint", () => {
+    for (const v of [undefined, null, "", "  ", "none", "NONE", "transparent", "rgba(0, 0, 0, 0)", "rgba(0,0,0,0)"]) {
+      assert.equal(isRealPaint(v), false, `${String(v)} should not paint`);
+    }
+  });
+  it("treats a color / currentColor as a real paint", () => {
+    for (const v of ["rgb(255, 255, 255)", "#000", "currentColor", "red", "rgb(0, 0, 0)"]) {
+      assert.equal(isRealPaint(v), true, `${v} should paint`);
+    }
+  });
+});
+
+describe("resolveSvgRootFill", () => {
+  it("keeps a raw fill that is itself a real paint", () => {
+    assert.deepEqual(resolveSvgRootFill("#123456", { fill: "rgb(255,255,255)", color: "rgb(0,0,0)" }), { mode: "keep" });
+    assert.deepEqual(resolveSvgRootFill("red", null), { mode: "keep" });
+  });
+
+  it("falls back when no raw fill is declared (existing currentColor default)", () => {
+    assert.deepEqual(resolveSvgRootFill(undefined, { fill: "rgb(255,255,255)", color: "rgb(255,255,255)" }), { mode: "fallback" });
+    assert.deepEqual(resolveSvgRootFill(null, null), { mode: "fallback" });
+  });
+
+  it("recovers currentColor when fill=none but computed fill tracks the element color (wordmark case)", () => {
+    // The a16z logo case: fill="none" attribute, but CSS `fill: currentColor` with white color.
+    const r = resolveSvgRootFill("none", { fill: "rgb(255, 255, 255)", color: "rgb(255, 255, 255)" });
+    assert.equal(r.mode, "emit");
+    assert.equal(r.value, "currentColor");
+    assert.equal(r.emitColor, "rgb(255, 255, 255)");
+  });
+
+  it("emits the literal computed fill when it differs from the element color", () => {
+    const r = resolveSvgRootFill("none", { fill: "rgb(255, 0, 0)", color: "rgb(0, 0, 0)" });
+    assert.equal(r.mode, "emit");
+    assert.equal(r.value, "rgb(255, 0, 0)");
+    assert.equal(r.emitColor, undefined);
+  });
+
+  it("leaves a genuinely unfilled svg as none (computed fill also none)", () => {
+    assert.deepEqual(resolveSvgRootFill("none", { fill: "none", color: "rgb(0,0,0)" }), { mode: "keep" });
+    assert.deepEqual(resolveSvgRootFill("none", { fill: "rgba(0, 0, 0, 0)", color: "rgb(0,0,0)" }), { mode: "keep" });
+    // No computed paint captured at all → cannot prove it paints → stays none.
+    assert.deepEqual(resolveSvgRootFill("none", null), { mode: "keep" });
+    assert.deepEqual(resolveSvgRootFill("none", undefined), { mode: "keep" });
+  });
+
+  it("does not emit color when the recovered fill is currentColor but color is not a real paint", () => {
+    // fill == color but color is transparent → cannot be a meaningful currentColor recovery;
+    // the equality branch is guarded on isRealPaint(color), so it emits the literal fill instead.
+    const r = resolveSvgRootFill("none", { fill: "rgb(0, 128, 0)", color: "transparent" });
+    assert.equal(r.mode, "emit");
+    assert.equal(r.value, "rgb(0, 128, 0)");
+    assert.equal(r.emitColor, undefined);
+  });
+});
diff --git a/compiler/test/tailwind.test.ts b/compiler/test/tailwind.test.ts
index dbd9938..d65cb4b 100644
--- a/compiler/test/tailwind.test.ts
+++ b/compiler/test/tailwind.test.ts
@@ -1,6 +1,6 @@
 import { describe, it } from "node:test";
 import assert from "node:assert/strict";
-import { declToUtil } from "../src/generate/tailwind.js";
+import { declToUtil, snapBase, prettifyBase, collapseBases } from "../src/generate/tailwind.js";
 
 // Zero-value gating. A named `-0` step only exists for props on Tailwind's spacing (or numeric)
 // scales; for the rest the class compiles to NOTHING — a silent no-op that ships the wrong style
@@ -41,3 +41,113 @@ describe("declToUtil zero values", () => {
     assert.equal(declToUtil("letter-spacing", "-0.5px"), "tracking-[-0.5px]");
   });
 });
+
+// BUG B — the spacing-scale snap must only fire when a value lands ESSENTIALLY ON a step (≤0.25px).
+// The scale is 2px-granular (`p-0.5`=2px, `p-1.5`=6px), so 3.5px is BETWEEN steps — snapping it up to
+// p-1 (4px) adds +0.5px per side, which accumulates across a fixed-width flex row until items overflow
+// and wrap. On-step values (2px→p-0.5, 4px→p-1) still snap.
+describe("snapBase spacing-scale snapping", () => {
+  it("keeps a between-steps value arbitrary (3.5px does NOT snap to p-1)", () => {
+    assert.equal(snapBase("p-[3.5px]"), "p-[3.5px]");
+  });
+
+  it("does not snap the same sub-step delta on other spacing props", () => {
+    assert.equal(snapBase("pl-[3.5px]"), "pl-[3.5px]");
+    assert.equal(snapBase("gap-[3.5px]"), "gap-[3.5px]");
+    assert.equal(snapBase("mt-[13.5px]"), "mt-[13.5px]"); // between p-3 (12px) and p-3.5 (14px)
+  });
+
+  it("still snaps a value that sits on a 0.5-step (2px → p-0.5, 6px → p-1.5)", () => {
+    assert.equal(snapBase("p-[2px]"), "p-0.5");
+    assert.equal(snapBase("p-[6px]"), "p-1.5");
+  });
+
+  it("still snaps a near-exact on-step value within the tight budget (3.98px → p-1)", () => {
+    assert.equal(snapBase("p-[3.98px]"), "p-1");
+  });
+
+  it("leaves an already-clean scale utility unchanged and snaps 16px → mx-4", () => {
+    assert.equal(snapBase("p-1"), "p-1");
+    assert.equal(snapBase("mx-[16px]"), "mx-4");
+  });
+});
+
+// A percentage 0 on a MAIN-SIZE axis (flex-basis) or a %-of-indefinite-height axis (height/min-height)
+// is NOT the definite zero `-0`: `flex-basis:0%` content-sizes against an auto-sized flex container,
+// whereas `flex-basis:0` gives a zero base size (collapsing a `flex:1 1 0%` item in an auto-height
+// column). prettifyBase must keep those literal. Width/inset 0% resolve against the definite
+// containing-block width, so their `-0` rewrite stays.
+describe("prettifyBase 0% on indefinite-axis prefixes", () => {
+  it("keeps basis-[0%] literal (0% ≠ definite 0 for flex-basis)", () => {
+    assert.equal(prettifyBase("basis-[0%]"), "basis-[0%]");
+  });
+  it("keeps h-[0%] and min-h-[0%] literal (%-of-indefinite-height → auto)", () => {
+    assert.equal(prettifyBase("h-[0%]"), "h-[0%]");
+    assert.equal(prettifyBase("min-h-[0%]"), "min-h-[0%]");
+  });
+  it("still rewrites width/inset 0% to the definite -0 (definite containing-block width)", () => {
+    assert.equal(prettifyBase("w-[0%]"), "w-0");
+    assert.equal(prettifyBase("min-w-[0%]"), "min-w-0");
+    assert.equal(prettifyBase("left-[0%]"), "left-0");
+    assert.equal(prettifyBase("inset-x-[0%]"), "inset-x-0");
+  });
+  it("still rewrites non-zero fractions on every prefix (basis-[33.3333%] → basis-1/3)", () => {
+    assert.equal(prettifyBase("basis-[33.3333%]"), "basis-1/3");
+    assert.equal(prettifyBase("h-[50%]"), "h-1/2");
+    assert.equal(prettifyBase("min-h-[100%]"), "min-h-full");
+  });
+});
+
+// flex:1 1 0% is Tailwind's `flex-1` — fold the grow-[1] + zero-basis pair so the emitted class both
+// reads idiomatically AND resolves to the exact flex longhands (avoiding the basis-[0%] hazard).
+describe("collapseBases flex-1 folding", () => {
+  it("folds grow-[1] + basis-[0%] → flex-1 (shrink defaults to 1, elided)", () => {
+    assert.deepEqual(collapseBases(["grow-[1]", "basis-[0%]"]), ["flex-1"]);
+  });
+  it("folds grow-[1] + basis-0 (already-shortened band delta) → flex-1", () => {
+    assert.deepEqual(collapseBases(["grow-[1]", "basis-0"]), ["flex-1"]);
+  });
+  it("does NOT fold when shrink-0 is present (flex:1 0 0% ≠ flex-1)", () => {
+    assert.deepEqual(collapseBases(["grow-[1]", "shrink-0", "basis-[0%]"]).sort(), ["basis-[0%]", "grow-[1]", "shrink-0"]);
+  });
+  it("does NOT fold a non-zero basis (grow-[1] + basis-[50%] left as-is)", () => {
+    assert.deepEqual(collapseBases(["grow-[1]", "basis-[50%]"]).sort(), ["basis-[50%]", "grow-[1]"]);
+  });
+});
+
+// letter-spacing is authored at a finer scale than box lengths; a real -0.08px tracking is within
+// snapLen's 0.1px integer-snap window and would collapse to 0px → Chromium serializes it as `normal`
+// → a false style-gate mismatch. Tracking must skip the integer snap (snapBase keeps 2 decimals).
+describe("declToUtil letter-spacing sub-0.1px preservation", () => {
+  it("keeps a real -0.08px tracking (does NOT snap to tracking-[0px])", () => {
+    assert.equal(declToUtil("letter-spacing", "-0.08px"), "tracking-[-0.08px]");
+  });
+  it("keeps -0.0375px through declToUtil, then snapBase rounds to 2 decimals (not to zero)", () => {
+    assert.equal(declToUtil("letter-spacing", "-0.0375px"), "tracking-[-0.0375px]");
+    assert.equal(snapBase("tracking-[-0.0375px]"), "tracking-[-0.04px]");
+  });
+  it("still keeps a genuine zero as tracking-[0px]", () => {
+    assert.equal(declToUtil("letter-spacing", "0px"), "tracking-[0px]");
+  });
+  it("still integer-snaps a BOX length near an integer (204.9994px → 205px)", () => {
+    assert.equal(declToUtil("width", "204.9994px"), "w-[205px]");
+  });
+});
+
+// text-wrap: modern heading line-balancing. `balance`/`pretty` rebalance where a title wraps;
+// without emitting them a two-line heading breaks differently in the clone. Tailwind v4 has the
+// named utilities text-balance / text-pretty / text-nowrap / text-wrap; anything else (e.g.
+// `stable`) falls through to the arbitrary property escape.
+describe("declToUtil text-wrap", () => {
+  it("maps balance and pretty to the named Tailwind v4 utilities", () => {
+    assert.equal(declToUtil("text-wrap", "balance"), "text-balance");
+    assert.equal(declToUtil("text-wrap", "pretty"), "text-pretty");
+  });
+  it("maps wrap and nowrap to their named utilities", () => {
+    assert.equal(declToUtil("text-wrap", "wrap"), "text-wrap");
+    assert.equal(declToUtil("text-wrap", "nowrap"), "text-nowrap");
+  });
+  it("falls back to the arbitrary property for an unmapped value", () => {
+    assert.equal(declToUtil("text-wrap", "stable"), "[text-wrap:stable]");
+  });
+});
diff --git a/compiler/test/videoSourceSelect.test.ts b/compiler/test/videoSourceSelect.test.ts
new file mode 100644
index 0000000..d144607
--- /dev/null
+++ b/compiler/test/videoSourceSelect.test.ts
@@ -0,0 +1,93 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { selectVideoSourceIndex, planVideoSeek, type VideoSourceCandidate } from "../src/capture/capture.js";
+
+// Predicate builders for the injected matchMedia / canPlayType.
+const matchesAny = (matching: Set<string>) => (m: string) => matching.has(m);
+const canPlayAll = () => true;
+const canPlayNone = () => false;
+
+describe("selectVideoSourceIndex (video <source> resource-selection)", () => {
+  it("picks the first source whose media matches; missing media matches unconditionally", () => {
+    // Aspect-gated hero: landscape sources first, portrait after, plain fall-through last.
+    const sources: VideoSourceCandidate[] = [
+      { media: "(min-aspect-ratio: 21/9)", type: "video/webm" },
+      { media: "(min-aspect-ratio: 16/9)", type: "video/webm" },
+      { media: "(max-aspect-ratio: 4/5)", type: "video/webm" },
+      { media: null, type: "video/webm" }, // plain fall-through
+    ];
+    // Portrait viewport: only the max-aspect-ratio query matches → index 2.
+    assert.equal(
+      selectVideoSourceIndex(sources, matchesAny(new Set(["(max-aspect-ratio: 4/5)"])), canPlayAll),
+      2,
+    );
+    // Landscape/wide viewport: the min-aspect 16/9 query matches → index 1.
+    assert.equal(
+      selectVideoSourceIndex(sources, matchesAny(new Set(["(min-aspect-ratio: 16/9)"])), canPlayAll),
+      1,
+    );
+    // Nothing matches → falls through to the plain no-media source (index 3).
+    assert.equal(selectVideoSourceIndex(sources, matchesAny(new Set()), canPlayAll), 3);
+  });
+
+  it("skips a source whose type the UA cannot play", () => {
+    const sources: VideoSourceCandidate[] = [
+      { media: null, type: "video/webm" }, // unplayable here
+      { media: null, type: "video/mp4" },
+    ];
+    const canPlayMp4 = (t: string) => t === "video/mp4";
+    assert.equal(selectVideoSourceIndex(sources, matchesAny(new Set()), canPlayMp4), 1);
+  });
+
+  it("treats a missing/empty type as never disqualifying", () => {
+    const sources: VideoSourceCandidate[] = [
+      { media: null, type: "" },
+      { media: null },
+    ];
+    // canPlay is never consulted when type is absent, even if it would reject everything.
+    assert.equal(selectVideoSourceIndex(sources, matchesAny(new Set()), canPlayNone), 0);
+  });
+
+  it("returns -1 when no source is eligible", () => {
+    const sources: VideoSourceCandidate[] = [
+      { media: "(max-aspect-ratio: 4/5)", type: "video/webm" },
+    ];
+    assert.equal(selectVideoSourceIndex(sources, matchesAny(new Set()), canPlayNone), -1);
+    assert.equal(selectVideoSourceIndex([], matchesAny(new Set()), canPlayAll), -1);
+  });
+
+  it("is deterministic and first-match-wins in document order", () => {
+    const sources: VideoSourceCandidate[] = [
+      { media: "(min-width: 100px)", type: "video/mp4" },
+      { media: "(min-width: 100px)", type: "video/mp4" }, // also eligible, but later
+    ];
+    assert.equal(selectVideoSourceIndex(sources, matchesAny(new Set(["(min-width: 100px)"])), canPlayAll), 0);
+  });
+});
+
+describe("planVideoSeek (post-reselection seek decision)", () => {
+  it("forces an epsilon seek on a reloaded video even at t=0 (clears the show-poster flag)", () => {
+    // The core regression: a just-reloaded video is at t=0 with the poster flag set. Seeking to 0
+    // fires no `seeked` and leaves the poster showing; only a genuine seek to a nonzero epsilon
+    // clears the flag and paints the new source's frame 0.
+    const plan = planVideoSeek(true, 0);
+    assert.ok(plan, "reloaded video must seek");
+    assert.ok(plan!.target > 0, "reloaded seek target must be nonzero so `seeked` actually fires");
+    assert.ok(plan!.target < 1e-3, "epsilon must be well inside frame 0");
+  });
+
+  it("still forces the epsilon seek on a reloaded video that reports a small nonzero time", () => {
+    const plan = planVideoSeek(true, 5e-4);
+    assert.deepEqual(plan, { target: 1e-4 });
+  });
+
+  it("fast-skips a non-reloaded video already at frame 0", () => {
+    assert.equal(planVideoSeek(false, 0), null);
+    assert.equal(planVideoSeek(false, 5e-4), null); // within the 1e-3 skip band
+  });
+
+  it("seeks a non-reloaded playing video back to 0", () => {
+    assert.deepEqual(planVideoSeek(false, 3.2), { target: 0 });
+    assert.deepEqual(planVideoSeek(false, 1e-3), { target: 0 }); // exactly at the band edge → seek
+  });
+});
diff --git a/compiler/test/viewportGraft.test.ts b/compiler/test/viewportGraft.test.ts
new file mode 100644
index 0000000..c55cf98
--- /dev/null
+++ b/compiler/test/viewportGraft.test.ts
@@ -0,0 +1,219 @@
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { mkdtempSync, mkdirSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import type { RawNode, RawChild } from "../src/capture/walker.js";
+import { buildIR, isTextChild, type IR, type IRNode } from "../src/normalize/ir.js";
+import { collectNodeRules } from "../src/generate/css.js";
+
+// Per-viewport DOM divergence handling:
+//  • GRAFT — a child that exists ONLY at non-canonical viewports enters the IR as a sibling at
+//    its source position, carrying per-viewport data only for the widths it appeared at, and is
+//    emitted display:none at base + revealed in its band(s).
+//  • DRIFT — a container whose children are a wholly DIFFERENT SET at some viewport (content
+//    identity drift) is NOT grafted (no duplication); the canonical children stand in at that
+//    width (the display:none banding is skipped) and the divergence is recorded in
+//    doc.contentDrift for the manifest.
+
+function raw(tag: string, attrs: Record<string, string> = {}, children: RawChild[] = [], visible = true, computedOver: Record<string, string> = {}): RawNode {
+  return {
+    tag, attrs,
+    computed: { display: visible ? "block" : "none", position: "static", visibility: "visible", ...computedOver },
+    bbox: { x: 0, y: 0, width: visible ? 640 : 0, height: visible ? 360 : 0 },
+    visible,
+    children,
+  };
+}
+
+function snapshot(vp: number, root: RawNode): object {
+  return {
+    doc: {
+      url: "https://example.test/page", title: "Fixture",
+      head: { description: "", canonical: "", ogTitle: "", ogDescription: "", ogImage: "", ogType: "", ogSiteName: "", twitterCard: "", themeColor: "" },
+      lang: "en", charset: "UTF-8", viewportWidth: vp, viewportHeight: 800,
+      scrollWidth: vp, scrollHeight: 800, htmlBg: "rgb(255, 255, 255)", bodyBg: "rgb(255, 255, 255)",
+      bodyColor: "rgb(0, 0, 0)", bodyFont: "Arial", metaViewport: "width=device-width, initial-scale=1",
+      nodeCount: 10, truncated: false,
+    },
+    root, cssVars: {}, fontFaces: [], cssUrls: [], domAssets: [], keyframes: [],
+  };
+}
+
+/** Build an IR from a DIFFERENT raw body tree per viewport. */
+function buildDivergentIR(rootByVp: Record<number, RawNode>): IR {
+  const vps = Object.keys(rootByVp).map(Number).sort((a, b) => a - b);
+  const sourceDir = mkdtempSync(join(tmpdir(), "ditto-ir-graft-"));
+  mkdirSync(join(sourceDir, "capture"), { recursive: true });
+  for (const vp of vps) {
+    writeFileSync(join(sourceDir, "capture", `dom-${vp}.json`), JSON.stringify(snapshot(vp, rootByVp[vp]!)));
+  }
+  return buildIR(sourceDir, vps);
+}
+
+function findByTag(node: IRNode, tag: string): IRNode | null {
+  if (node.tag === tag) return node;
+  for (const c of node.children) {
+    if (isTextChild(c)) continue;
+    const hit = findByTag(c, tag);
+    if (hit) return hit;
+  }
+  return null;
+}
+
+function elemChildren(node: IRNode): IRNode[] {
+  return node.children.filter((c): c is IRNode => !isTextChild(c));
+}
+
+// ---- fixtures ----
+
+/** Carousel whose pagination (ul + 3 bullet li) exists ONLY below the canonical width. */
+function carouselFixture(): { small: RawNode; large: RawNode } {
+  const track = (): RawNode => raw("div", { id: "track" });
+  const pagination = (): RawNode =>
+    raw("ul", { id: "pagination" }, [
+      raw("li", {}, [raw("button", { type: "button" }, [{ text: "1" }])]),
+      raw("li", {}, [raw("button", { type: "button" }, [{ text: "2" }])]),
+      raw("li", {}, [raw("button", { type: "button" }, [{ text: "3" }])]),
+    ]);
+  const small = raw("body", {}, [raw("section", { id: "carousel" }, [track(), pagination()])]);
+  const large = raw("body", {}, [raw("section", { id: "carousel" }, [track()])]);
+  return { small, large };
+}
+
+/** Container serving a DIFFERENT item set per viewport (content identity drift). */
+function driftFixture(): { small: RawNode; large: RawNode } {
+  const item = (id: string): RawNode => raw("li", { id }, [raw("span", {}, [{ text: `Item ${id}` }])]);
+  const small = raw("body", {}, [raw("ul", { id: "rotator" }, [item("b1"), item("b2"), item("b3"), item("b4")])]);
+  const large = raw("body", {}, [raw("ul", { id: "rotator" }, [item("a1"), item("a2"), item("a3"), item("a4")])]);
+  return { small, large };
+}
+
+describe("IR grafts non-canonical-only children", () => {
+  it("grafts a subtree present only at 375 into the canonical tree at its source position", () => {
+    const { small, large } = carouselFixture();
+    const ir = buildDivergentIR({ 375: small, 1280: large });
+
+    const section = findByTag(ir.root, "section")!;
+    const kids = elemChildren(section);
+    assert.deepEqual(kids.map((k) => k.tag), ["div", "ul"], "pagination grafted after the matched track");
+
+    const ul = kids[1]!;
+    assert.equal(ul.attrs.id, "pagination");
+    // Per-viewport data ONLY at the source viewport — nothing invented at canonical.
+    assert.deepEqual(Object.keys(ul.computedByVp), ["375"]);
+    assert.equal(ul.visibleByVp[375], true);
+    assert.equal(ul.computedByVp[1280], undefined);
+    assert.equal(ul.bboxByVp[1280], undefined);
+    // The grafted subtree's descendants carry the same viewport-scoped data.
+    const bullets = elemChildren(ul);
+    assert.equal(bullets.length, 3);
+    for (const li of bullets) {
+      assert.deepEqual(Object.keys(li.computedByVp), ["375"]);
+      const btn = elemChildren(li)[0]!;
+      assert.equal(btn.tag, "button");
+      assert.deepEqual(Object.keys(btn.computedByVp), ["375"]);
+    }
+    // No drift recorded — this is an additive responsive difference, not a set swap.
+    assert.equal(section.childDriftVps, undefined);
+    assert.equal(ir.doc.contentDrift, undefined);
+  });
+
+  it("merges the same non-canonical-only child across several viewports into ONE grafted node", () => {
+    const { small, large } = carouselFixture();
+    const ir = buildDivergentIR({ 375: small, 768: structuredClone(small), 1280: large });
+
+    const section = findByTag(ir.root, "section")!;
+    const uls = elemChildren(section).filter((k) => k.tag === "ul");
+    assert.equal(uls.length, 1, "one grafted node, not one per viewport");
+    assert.deepEqual(Object.keys(uls[0]!.computedByVp).map(Number).sort((a, b) => a - b), [375, 768]);
+  });
+
+  it("is deterministic: two builds from the same capture are byte-identical", () => {
+    const { small, large } = carouselFixture();
+    const a = buildDivergentIR({ 375: small, 1280: large });
+    const b = buildDivergentIR({ 375: structuredClone(small), 1280: structuredClone(large) });
+    assert.equal(JSON.stringify(a), JSON.stringify(b));
+  });
+
+  it("does not graft a child that never paints at any band viewport", () => {
+    const { small, large } = carouselFixture();
+    // Make the whole pagination subtree invisible at 375.
+    const section = small.children[0] as RawNode;
+    const pag = (section.children as RawNode[]).find((c) => c.tag === "ul")!;
+    const markInvisible = (n: RawNode): void => {
+      n.visible = false; n.computed.display = "none"; n.bbox = { x: 0, y: 0, width: 0, height: 0 };
+      for (const c of n.children) if ((c as RawNode).tag) markInvisible(c as RawNode);
+    };
+    markInvisible(pag);
+    const ir = buildDivergentIR({ 375: small, 1280: large });
+    assert.equal(findByTag(ir.root, "ul"), null, "invisible-everywhere subtree is not grafted");
+  });
+});
+
+describe("IR whole-set content drift falls back to faithful-at-canonical", () => {
+  it("records drift instead of grafting when both sides mutually mismatch", () => {
+    const { small, large } = driftFixture();
+    const ir = buildDivergentIR({ 375: small, 1280: large });
+
+    const rotator = findByTag(ir.root, "ul")!;
+    const kids = elemChildren(rotator);
+    // Canonical set only — the divergent 375 set is NOT grafted (no duplication).
+    assert.deepEqual(kids.map((k) => k.attrs.id), ["a1", "a2", "a3", "a4"]);
+    assert.deepEqual(rotator.childDriftVps, [375]);
+    // Canonical children carry no invented data at the drift viewport.
+    for (const k of kids) assert.equal(k.computedByVp[375], undefined);
+    // Surfaced for the manifest, with the final (post-renumber) id.
+    assert.deepEqual(ir.doc.contentDrift, [{ id: rotator.id, tag: "ul", viewports: [375] }]);
+  });
+
+  it("does not misread an additive difference as drift", () => {
+    // Canonical set fully matches at 375; 375 merely has extras → graft path, no drift.
+    const item = (id: string): RawNode => raw("li", { id });
+    const small = raw("body", {}, [raw("ul", { id: "list" }, [item("x1"), item("x2"), item("e1"), item("e2"), item("e3")])]);
+    const large = raw("body", {}, [raw("ul", { id: "list" }, [item("x1"), item("x2")])]);
+    const ir = buildDivergentIR({ 375: small, 1280: large });
+    const list = findByTag(ir.root, "ul")!;
+    assert.equal(list.childDriftVps, undefined);
+    assert.deepEqual(elemChildren(list).map((k) => k.attrs.id), ["x1", "x2", "e1", "e2", "e3"]);
+    assert.deepEqual(Object.keys(elemChildren(list)[2]!.computedByVp), ["375"]);
+  });
+});
+
+describe("emission of grafted and drift nodes", () => {
+  it("emits a grafted node as display:none at base with a full reveal band at its viewport", () => {
+    const { small, large } = carouselFixture();
+    const ir = buildDivergentIR({ 375: small, 1280: large });
+    const ul = findByTag(ir.root, "ul")!;
+    const rules = collectNodeRules(ir, new Map());
+    const nr = rules.get(ul.id)!;
+    assert.deepEqual([...nr.base.entries()], [["display", "none"]], "hidden at the canonical base");
+    assert.equal(nr.bands.length, 1, "exactly one band: the reveal at its source viewport");
+    const band = nr.bands[0]!;
+    assert.match(band.media, /max-width/);
+    assert.equal(band.decls.get("display"), "block", "the band reveals AND lays out the node");
+  });
+
+  it("skips the display:none band for drift stand-ins (and their descendants), keeps it otherwise", () => {
+    const { small, large } = driftFixture();
+    // Control: a genuinely canonical-only sibling (absent at 375, NOT under a drift container)
+    // must still be banded display:none at 375.
+    (large.children as RawNode[]).push(raw("aside", { id: "desktop-only" }, [{ text: "Desktop" }]));
+    const ir = buildDivergentIR({ 375: small, 1280: large });
+    const rules = collectNodeRules(ir, new Map());
+
+    const rotator = findByTag(ir.root, "ul")!;
+    for (const li of elemChildren(rotator)) {
+      const nr = rules.get(li.id)!;
+      assert.equal(nr.bands.some((b) => b.decls.get("display") === "none"), false, `stand-in ${li.attrs.id} not hidden at the drift viewport`);
+      // Descendants of the stand-in subtree are not hidden either.
+      const span = elemChildren(li)[0]!;
+      const snr = rules.get(span.id)!;
+      assert.equal(snr.bands.some((b) => b.decls.get("display") === "none"), false, "stand-in descendant not hidden");
+    }
+
+    const aside = findByTag(ir.root, "aside")!;
+    const anr = rules.get(aside.id)!;
+    assert.equal(anr.bands.some((b) => b.decls.get("display") === "none"), true, "unrelated canonical-only node still hidden per band");
+  });
+});
diff --git a/compiler/test/walker.test.ts b/compiler/test/walker.test.ts
index a681f7c..5bc48dd 100644
--- a/compiler/test/walker.test.ts
+++ b/compiler/test/walker.test.ts
@@ -158,3 +158,358 @@ describe("walker off-screen visibility", () => {
     assert.equal(fixed.visible, false, "fixed box below the viewport is invisible");
   });
 });
+
+describe("walker font-metric probe tagging (fix 4)", () => {
+  let browser: Browser;
+  let page: Page;
+  before(async () => {
+    browser = await chromium.launch();
+    page = await browser.newPage();
+    await page.setViewportSize({ width: 375, height: 768 });
+  });
+  after(async () => {
+    await browser.close();
+  });
+
+  const capture = async (html: string) => {
+    await page.setContent(html);
+    await page.evaluate("globalThis.__name = globalThis.__name || ((fn) => fn);");
+    return page.evaluate(collectPage);
+  };
+
+  it("tags a far-off-screen, non-painting measurement scratch node as a probe", async () => {
+    // The classic font-metric probe pattern (WordPress/typography libs): absolutely positioned,
+    // parked ~100000px off-screen, visibility:hidden, holding measurement text.
+    const snap = await capture(`
+      <p class="real">Real content</p>
+      <div class="probe" style="position:absolute;top:-99999px;left:-99999px;
+           visibility:hidden;white-space:nowrap;">Mgy</div>`);
+    const probe = findByClass(snap.root, "probe")!;
+    assert.equal(probe.probe, true, "far-off-screen hidden scratch node is a probe");
+    const real = findByClass(snap.root, "real")!;
+    assert.ok(!real.probe, "real content is not a probe");
+  });
+
+  it("does NOT tag a near-off-screen hidden drawer (real content) as a probe", async () => {
+    // A slide-in drawer parked just off the left edge (x:-375, visibility:hidden) is real
+    // content that a controller can reveal — it must NOT be mistaken for a measurement probe.
+    const snap = await capture(`
+      <div class="drawer" style="position:fixed;left:0;top:0;width:375px;height:768px;
+           transform:translateX(-100%);visibility:hidden;">
+        <h2 class="dtitle">Menu</h2>
+      </div>`);
+    const drawer = findByClass(snap.root, "drawer")!;
+    assert.ok(!drawer.probe, "a near-off-screen drawer is not a probe");
+  });
+
+  it("does NOT tag an sr-only (visible, on-screen-adjacent) accessibility label as a probe", async () => {
+    // Screen-reader-only text stays visibility:visible so AT can read it; even parked far off
+    // via left:-9999px it must survive (and 9999px is under the 10000px probe threshold anyway).
+    const snap = await capture(`
+      <a href="/"><span class="sr" style="position:absolute;left:-9999px;">Skip to content</span>Home</a>`);
+    const sr = findByClass(snap.root, "sr")!;
+    assert.ok(!sr.probe, "sr-only accessible text is not a probe");
+  });
+});
+
+describe("walker sizing probe: circular authored-height guard", () => {
+  let browser: Browser;
+  let page: Page;
+  before(async () => {
+    browser = await chromium.launch();
+    page = await browser.newPage({ viewport: { width: 1280, height: 720 } });
+  });
+  after(async () => {
+    await browser.close();
+  });
+
+  const capture = async (html: string) => {
+    await page.setContent(html);
+    await page.evaluate("globalThis.__name = globalThis.__name || ((fn) => fn);");
+    return page.evaluate(collectPage);
+  };
+
+  it("keeps an explicit 100vh height (circular hero/fill-child pair)", async () => {
+    // A hero authored `height:100vh` with a `height:100%` fill child: setting the hero to
+    // `height:auto` still reproduces its box because the child pins it back, so the raw probe
+    // would read hAuto:true and the authored 100vh would be dropped — hero collapses to 0.
+    const snap = await capture(`
+      <style>
+        .hero { height: 100vh; display: flex; }
+        .fill { height: 100%; width: 100%; }
+      </style>
+      <section class="hero"><div class="fill"><p>content</p></div></section>`);
+    const hero = findByClass(snap.root, "hero")!;
+    assert.ok(hero.sizing, "hero was probed");
+    assert.equal(hero.sizing!.hAuto, false, "explicit 100vh is not content-sized");
+    assert.equal(hero.sizing!.hFill, false, "explicit 100vh is authored, not a parent fill");
+    // Box actually equals the viewport height (720), proving the circular reproduction.
+    assert.ok(Math.abs(hero.bbox.height - 720) <= 1, "hero rendered at 100vh");
+  });
+
+  it("keeps an explicit px height whose fill child reproduces it", async () => {
+    const snap = await capture(`
+      <style>
+        .section { height: 400px; display: flex; }
+        .fill { height: 100%; width: 100%; }
+      </style>
+      <div class="section"><div class="fill"><p>content</p></div></div>`);
+    const section = findByClass(snap.root, "section")!;
+    assert.ok(section.sizing, "section was probed");
+    assert.equal(section.sizing!.hAuto, false, "explicit 400px is not content-sized");
+    assert.equal(section.sizing!.hFill, false, "explicit 400px is authored, not a fill");
+    assert.ok(Math.abs(section.bbox.height - 400) <= 1, "section rendered at 400px");
+  });
+
+  it("keeps an explicit height authored via inline style", async () => {
+    const snap = await capture(`
+      <style>.fill { height: 100%; width: 100%; }</style>
+      <div class="box" style="height: 300px; display: flex;">
+        <div class="fill"><p>content</p></div>
+      </div>`);
+    const box = findByClass(snap.root, "box")!;
+    assert.ok(box.sizing, "box was probed");
+    assert.equal(box.sizing!.hAuto, false, "inline explicit height is kept");
+    assert.equal(box.sizing!.hFill, false, "inline explicit height is not a fill");
+  });
+
+  it("resolves the mutual parent/child pair without disturbing the fill child", async () => {
+    // The child is a GENUINE fill (height:100%) and must keep hFill:true / hAuto:false so the
+    // generator emits h-full for it; only the parent's circular verdict is corrected.
+    const snap = await capture(`
+      <style>
+        .outer { height: 500px; display: flex; }
+        .inner { height: 100%; width: 100%; }
+      </style>
+      <div class="outer"><div class="inner"><p>content</p></div></div>`);
+    const outer = findByClass(snap.root, "outer")!;
+    const inner = findByClass(snap.root, "inner")!;
+    assert.equal(outer.sizing!.hAuto, false, "parent explicit height kept");
+    assert.equal(outer.sizing!.hFill, false, "parent is authored, not a fill");
+    // The child authors only `height:100%` (a fill), so the explicit-height guard must NOT fire on
+    // it — hFill stays true so the generator can still emit h-full for the genuine fill child.
+    assert.equal(inner.sizing!.hFill, true, "child still fills the definite parent");
+  });
+
+  it("still detects a genuinely content-sized (auto) height as hAuto", async () => {
+    // No authored height anywhere: the box is content-sized and must stay droppable.
+    const snap = await capture(`
+      <style>.wrap { display: block; }</style>
+      <div class="wrap"><p>just some flowing text content</p></div>`);
+    const wrap = findByClass(snap.root, "wrap")!;
+    assert.ok(wrap.sizing, "wrap was probed");
+    assert.equal(wrap.sizing!.hAuto, true, "content-sized height is still auto");
+  });
+
+  it("does not treat a percentage or zero authored height as explicit", async () => {
+    // height:100% is the FILL case (handled by hFill), and height:0 is not definite; neither
+    // should trip the explicit-height override.
+    const snap = await capture(`
+      <style>
+        .pct-parent { height: 300px; }
+        .pct { height: 100%; }
+      </style>
+      <div class="pct-parent"><div class="pct"><p>x</p></div></div>`);
+    const pct = findByClass(snap.root, "pct")!;
+    assert.ok(pct.sizing, "pct was probed");
+    // A true fill child: hFill true, hAuto false — untouched by the explicit-height guard.
+    assert.equal(pct.sizing!.hFill, true, "percentage height stays a fill");
+    assert.equal(pct.sizing!.hAuto, false, "percentage fill is not content-sized");
+  });
+});
+
+// T4 — symmetric circular-WIDTH guard: an authored `width:24px` inside a SHRINK-TO-FIT parent makes
+// both width:auto and width:100% reproduce the box (the parent's width still holds), so the raw probe
+// reads wAuto/wFill and the width is dropped — collapsing the swatch in the clone. When the element
+// authors an explicit definite width (cascade or inline), the probe must trust that and clear both.
+describe("walker sizing probe: circular authored-width guard (T4)", () => {
+  let browser: Browser;
+  let page: Page;
+  before(async () => {
+    browser = await chromium.launch();
+    page = await browser.newPage({ viewport: { width: 1280, height: 720 } });
+  });
+  after(async () => {
+    await browser.close();
+  });
+
+  const capture = async (html: string) => {
+    await page.setContent(html);
+    await page.evaluate("globalThis.__name = globalThis.__name || ((fn) => fn);");
+    return page.evaluate(collectPage);
+  };
+
+  it("keeps an explicit px width inside a shrink-wrap parent (cascade rule)", async () => {
+    // The wrapper is an inline-block that shrink-wraps to the swatch; width:auto on the swatch still
+    // reads 24px because the parent width holds → the raw verdict would be wAuto:true (dropped).
+    const snap = await capture(`
+      <style>
+        .wrapper { display: inline-block; border: 1px solid #000; }
+        .swatch { width: 24px; height: 24px; display: block; background: red; }
+      </style>
+      <span class="wrapper"><a class="swatch"></a></span>`);
+    const swatch = findByClass(snap.root, "swatch")!;
+    assert.ok(swatch.sizing, "swatch was probed");
+    assert.equal(swatch.sizing!.wAuto, false, "explicit 24px width is not content-sized (auto)");
+    assert.equal(swatch.sizing!.wFill, false, "explicit 24px width is authored, not a parent fill");
+  });
+
+  it("keeps an explicit width authored via inline style", async () => {
+    const snap = await capture(`
+      <span style="display:inline-block;border:1px solid #000;">
+        <a class="swatch2" style="width:24px;height:24px;display:block;background:blue;"></a>
+      </span>`);
+    const swatch = findByClass(snap.root, "swatch2")!;
+    assert.ok(swatch.sizing, "swatch was probed");
+    assert.equal(swatch.sizing!.wAuto, false, "inline explicit width is kept (not auto)");
+    assert.equal(swatch.sizing!.wFill, false, "inline explicit width is not a fill");
+  });
+
+  it("still detects a genuinely content-sized (auto) width as wAuto", async () => {
+    // No authored width: an inline-block sizing to its text must stay droppable (wAuto:true).
+    const snap = await capture(`
+      <div style="display:block;"><span class="cw" style="display:inline-block;">hello content</span></div>`);
+    const cw = findByClass(snap.root, "cw")!;
+    assert.ok(cw.sizing, "cw was probed");
+    assert.equal(cw.sizing!.wAuto, true, "content-sized width is still auto");
+  });
+
+  it("harvests an explicit-width rule from a custom element's SHADOW ROOT stylesheet", async () => {
+    // The width:24px rule lives inside the custom element's shadow root (a <style> in the shadow tree),
+    // never in document.styleSheets. Without walking shadow-root sheets the harvest misses it and the
+    // circular-width guard can't fire for the swatch link. Verify the shadow swatch keeps its width.
+    const snap = await capture(`
+      <script>
+        customElements.define('color-swatch', class extends HTMLElement {
+          constructor() {
+            super();
+            const r = this.attachShadow({ mode: 'open' });
+            r.innerHTML = '<style>.wrap{display:inline-block;border:1px solid #000}.pin{width:24px;height:24px;display:block;background:green}</style><span class="wrap"><a class="pin"></a></span>';
+          }
+        });
+      </script>
+      <color-swatch></color-swatch>`);
+    const pin = findByClass(snap.root, "pin")!;
+    assert.ok(pin.sizing, "shadow swatch was probed");
+    assert.equal(pin.sizing!.wAuto, false, "shadow-root explicit 24px width is kept (not auto)");
+    assert.equal(pin.sizing!.wFill, false, "shadow-root explicit width is not a fill");
+  });
+});
+
+describe("walker text-wrap capture", () => {
+  let browser: Browser;
+  let page: Page;
+  before(async () => {
+    browser = await chromium.launch();
+    page = await browser.newPage({ viewport: { width: 1280, height: 800 } });
+  });
+  after(async () => {
+    await browser.close();
+  });
+
+  const capture = async (html: string) => {
+    await page.setContent(html);
+    await page.evaluate("globalThis.__name = globalThis.__name || ((fn) => fn);");
+    return page.evaluate(collectPage);
+  };
+
+  it("captures text-wrap:balance on a heading (modern line-balancing)", async () => {
+    // Real case: a hero heading authored `text-wrap:balance` wraps its two lines evenly; without
+    // capturing the prop the clone wraps it lopsidedly.
+    const snap = await capture(`<h1 style="text-wrap:balance">BUILT RUGGED. WORN DAILY.</h1>`);
+    const h1 = findByTag(snap.root, "h1")!;
+    assert.equal(h1.computed.textWrap, "balance", "text-wrap:balance is captured");
+  });
+
+  it("captures text-wrap:pretty", async () => {
+    const snap = await capture(`<p style="text-wrap:pretty">Some flowing paragraph text here.</p>`);
+    const p = findByTag(snap.root, "p")!;
+    assert.equal(p.computed.textWrap, "pretty", "text-wrap:pretty is captured");
+  });
+});
+
+describe("walker shadow-DOM composed-tree serialization (FIX 1)", () => {
+  let browser: Browser;
+  let page: Page;
+  before(async () => {
+    browser = await chromium.launch();
+    page = await browser.newPage({ viewport: { width: 1280, height: 800 } });
+  });
+  after(async () => {
+    await browser.close();
+  });
+
+  // Attach an OPEN shadow root to any host carrying data-shadow, injecting its data-shadow value as
+  // the shadow tree HTML. Runs in-page before collectPage so getComputedStyle/bbox see the composed tree.
+  const capture = async (html: string) => {
+    await page.setContent(html);
+    await page.evaluate(() => {
+      for (const host of Array.from(document.querySelectorAll("[data-shadow]"))) {
+        const markup = host.getAttribute("data-shadow") || "";
+        const sr = (host as HTMLElement).attachShadow({ mode: "open" });
+        sr.innerHTML = markup;
+      }
+    });
+    await page.evaluate("globalThis.__name = globalThis.__name || ((fn) => fn);");
+    return page.evaluate(collectPage);
+  };
+
+  it("serializes an open custom element's shadow tree as the host's children", async () => {
+    // A `<product-info>` web component renders its swatches/title/price INSIDE its shadow root; a
+    // childNodes-only walk captured it empty. The composed walk must surface the shadow content.
+    const snap = await capture(`
+      <product-info data-shadow="
+        <div class='pi-title'>Magnolia Shirt</div>
+        <span class='pi-price'>$78.00</span>
+      "></product-info>`);
+    const host = findByTag(snap.root, "product-info")!;
+    assert.ok(host, "the custom element host is present");
+    assert.equal(host.shadowHost, true, "the host is tagged as a shadow host");
+    assert.equal(textRun(host).replace(/\s+/g, " ").trim(), "Magnolia Shirt $78.00", "the shadow tree text is captured");
+    const title = findByClass(host, "pi-title")!;
+    assert.ok(title, "a shadow descendant node is serialized");
+    assert.equal(title.inShadow, true, "shadow descendants are tagged inShadow");
+    assert.ok(title.bbox.width > 0, "shadow nodes get real bboxes via getBoundingClientRect");
+  });
+
+  it("renders the FLATTENED tree: a <slot> is replaced by its assigned light-DOM nodes", async () => {
+    // The host's light child (the assigned node) renders at the slot position — once, and NOT tagged
+    // inShadow (it is the author's real content). Shadow chrome around the slot still appears.
+    const snap = await capture(`
+      <my-card data-shadow="
+        <div class='card-frame'><slot></slot></div>
+      "><h2 class='slotted'>Vintage Sunset T-Shirt</h2></my-card>`);
+    const host = findByTag(snap.root, "my-card")!;
+    const frame = findByClass(host, "card-frame")!;
+    assert.ok(frame, "the shadow frame around the slot is serialized");
+    assert.equal(frame.inShadow, true, "the shadow frame is tagged inShadow");
+    const slotted = findByClass(host, "slotted")!;
+    assert.ok(slotted, "the slotted light child renders at the slot position");
+    assert.equal(textRun(slotted).trim(), "Vintage Sunset T-Shirt");
+    assert.ok(!slotted.inShadow, "the slotted light child is NOT tagged inShadow (author content)");
+    // No double-serialization: exactly one node carries the slotted text.
+    let count = 0;
+    const countText = (n: RawNode): void => {
+      if (n.children.some((c) => isText(c) && c.text.includes("Vintage Sunset T-Shirt"))) count++;
+      for (const c of n.children) if (!isText(c)) countText(c as RawNode);
+    };
+    countText(host);
+    assert.equal(count, 1, "the slotted child is serialized exactly once");
+  });
+
+  it("uses <slot> fallback content when nothing is assigned", async () => {
+    const snap = await capture(`
+      <my-badge data-shadow="
+        <span class='badge'><slot>Default Label</slot></span>
+      "></my-badge>`);
+    const host = findByTag(snap.root, "my-badge")!;
+    assert.equal(textRun(host).replace(/\s+/g, " ").trim(), "Default Label", "unfilled slot falls back to its own content");
+  });
+
+  it("does not tag ordinary light-DOM nodes as shadow", async () => {
+    const snap = await capture(`<div class="plain"><p>light</p></div>`);
+    const plain = findByClass(snap.root, "plain")!;
+    assert.ok(!plain.shadowHost, "a plain div is not a shadow host");
+    assert.ok(!plain.inShadow, "plain light DOM is not tagged inShadow");
+  });
+});