diff --git a/frontend/scripts/measure-home-first-load.mjs b/frontend/scripts/measure-home-first-load.mjs
index 55601653..31e12511 100644
--- a/frontend/scripts/measure-home-first-load.mjs
+++ b/frontend/scripts/measure-home-first-load.mjs
@@ -14,6 +14,11 @@
  *
  *   /exec-daemon/node scripts/measure-home-first-load.mjs --base http://127.0.0.1:3920 --delay 600 [--runs 3] [--port 9340] [--throttle slow]
  *
+ * `--css-delay 1500` holds every stylesheet response that long (TASK-home-first-load-fix
+ * -20261001): an inline script after the stylesheets waits for them, which a
+ * local server hides because CSS arrives instantly.
+ * `--ua iphone` uses an iPhone Safari user agent (headless Chrome engine, not WebKit).
+ *
  * `--throttle slow` emulates 1.6 Mbps down / 150 ms latency so JS and font
  * downloads cost something against a local server. "First-screen JS" is the
  * scripts the HTML itself references (parser-initiated), not chunks loaded later.
@@ -30,6 +35,9 @@ const BASE = (args.base ?? "http://127.0.0.1:3000").replace(/\/$/, "");
 const DELAY = Number(args.delay ?? 600);
 const RUNS = Number(args.runs ?? 1);
 const PORT = Number(args.port ?? 9340);
+const CSS_DELAY = Number(args["css-delay"] ?? 0);
+const IPHONE_UA = "Mozilla/5.0 (iPhone; CPU iPhone OS 18_0 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.0 Mobile/15E148 Safari/604.1";
+const UA = args.ua === "iphone" ? IPHONE_UA : null;
 const THROTTLE = args.throttle === "slow" ? { offline: false, latency: 150, downloadThroughput: 1_600_000 / 8, uploadThroughput: 750_000 / 8 } : null;
 
 const ACCOUNT = JSON.stringify({
@@ -72,6 +80,7 @@ async function measureOnce() {
   const urls = new Map();
   const jsDone = [];
   const parserJs = new Set();
+  const cssReleased = [];
   const apiStarts = [];
   ws.onmessage = (message) => {
     const m = JSON.parse(message.data);
@@ -86,6 +95,12 @@ async function measureOnce() {
           events.push([at, `api ${m.params.request.method} ${url.replace(/^https?:\/\/[^/]+/, "").slice(0, 60)} → ${status} (answered ${now()}ms)`]);
           void send("Fetch.fulfillRequest", { requestId: m.params.requestId, responseCode: status, responseHeaders: [{ name: "content-type", value: "application/json" }], body: Buffer.from(body).toString("base64") });
         }, DELAY);
+      } else if (CSS_DELAY > 0 && /\.css(\?|$)/.test(url)) {
+        setTimeout(() => {
+          events.push([now(), `stylesheet released ${url.split("/").pop().split("?")[0]}`]);
+          cssReleased.push(now());
+          void send("Fetch.continueRequest", { requestId: m.params.requestId });
+        }, CSS_DELAY);
       } else {
         void send("Fetch.continueRequest", { requestId: m.params.requestId });
       }
@@ -103,6 +118,10 @@ async function measureOnce() {
   await send("Fetch.enable", { patterns: [{ urlPattern: "*" }] });
   await send("Network.enable");
   if (THROTTLE) await send("Network.emulateNetworkConditions", THROTTLE);
+  if (UA) {
+    await send("Network.setUserAgentOverride", { userAgent: UA, platform: "iPhone" });
+    await send("Emulation.setDeviceMetricsOverride", { width: 390, height: 844, deviceScaleFactor: 3, mobile: true });
+  }
   await send("Page.enable");
   t0 = performance.now();
   await send("Page.navigate", { url: `${BASE}/` });
@@ -129,8 +148,10 @@ async function measureOnce() {
     if (revealed !== null && at > revealed) break;
     if (!waves.length || at - waves[waves.length - 1] > DELAY / 2) waves.push(at);
   }
+  const bootReads = await send("Runtime.evaluate", { expression: `(() => { const r = window.__jyotishaBootReads; return r === undefined ? "absent" : JSON.stringify(Object.keys(r)); })()`, returnByValue: true });
+  const firstCss = cssReleased.length ? Math.min(...cssReleased) : null;
   chrome.kill();
-  return { events, summary: { revealed, lastJs, firstApi, firstApiVsLastJs: firstApi !== null && lastJs !== null ? firstApi - lastJs : null, apiRounds: waves.length, serifFontRequestsBeforeLoad: fontsBeforeLoad } };
+  return { events, summary: { firstStylesheetReleased: firstCss, firstApiBeforeCss: firstCss !== null && firstApi !== null ? firstApi < firstCss : null, bootReadsAfterReveal: bootReads?.result?.value ?? null, revealed, lastJs, firstApi, firstApiVsLastJs: firstApi !== null && lastJs !== null ? firstApi - lastJs : null, apiRounds: waves.length, serifFontRequestsBeforeLoad: fontsBeforeLoad } };
 }
 
 const summaries = [];
diff --git a/frontend/src/app/layout.tsx b/frontend/src/app/layout.tsx
index 0aaeb1fd..049f4492 100644
--- a/frontend/src/app/layout.tsx
+++ b/frontend/src/app/layout.tsx
@@ -5,7 +5,7 @@ import { Toaster } from "@/components/ui/sonner";
 import { StaleBuildGuard } from "@/components/stale-build-guard";
 import { StaleClientRecovery } from "@/components/stale-client-recovery";
 import { ViewportScrollLock } from "@/components/viewport-scroll-lock";
-import { bootEarlyReadsScript } from "@/lib/boot-early-reads";
+import { bootEarlyReadsScriptSrc } from "@/lib/boot-early-reads";
 import { firstPaintFallbackBootScript } from "@/lib/first-paint-fallback";
 import { themePreferenceBootScript } from "@/lib/theme-preference";
 
@@ -59,8 +59,10 @@ export default function RootLayout({ children }: Readonly<{ children: React.Reac
         {/* Classic script, not a module: it has to run when the client bundle never does. */}
         <script dangerouslySetInnerHTML={{ __html: firstPaintFallbackBootScript() }} />
         {/* Home cold-boot reads leave with the HTML instead of after the bundle
-            runs (BUG-1127). The script is a no-op on every path except "/". */}
-        <script dangerouslySetInnerHTML={{ __html: bootEarlyReadsScript() }} />
+            runs (BUG-1127). The script is a no-op on every path except "/".
+            async + data: URL, not inline: an inline script after the
+            stylesheets would wait for them to download (fix 2026-10-01). */}
+        <script async src={bootEarlyReadsScriptSrc()} />
         {enableReactDevTools && (
           <>
             <Script
diff --git a/frontend/src/lib/boot-early-reads.ts b/frontend/src/lib/boot-early-reads.ts
index 06cfe5bc..0c3357ee 100644
--- a/frontend/src/lib/boot-early-reads.ts
+++ b/frontend/src/lib/boot-early-reads.ts
@@ -78,6 +78,18 @@ export function bootEarlyReadsScript(): string {
 })();`;
 }
 
+/**
+ * The script as an async data: URL (BUG-1127 fix, 2026-10-01). An inline
+ * classic script placed after the page's stylesheets waits until they have
+ * downloaded (script-blocking stylesheets), which on staging held the early
+ * reads back 2.4-3.1 s. An `async` external classic script is not blocked by
+ * stylesheets, and a data: URL costs no round trip. Plain ASCII base64, so
+ * the attribute needs no escaping.
+ */
+export function bootEarlyReadsScriptSrc(): string {
+  return `data:text/javascript;base64,${Buffer.from(bootEarlyReadsScript(), "utf8").toString("base64")}`;
+}
+
 function bootReads(): BootReads | null {
   if (typeof window === "undefined") return null;
   const reads = (window as unknown as Record<string, BootReads | undefined>)[BOOT_READS_GLOBAL];
diff --git a/frontend/tests/home-first-load-20260930.test.tsx b/frontend/tests/home-first-load-20260930.test.tsx
index 4f222795..abfdde4b 100644
--- a/frontend/tests/home-first-load-20260930.test.tsx
+++ b/frontend/tests/home-first-load-20260930.test.tsx
@@ -8,7 +8,7 @@ import { renderToStaticMarkup } from "react-dom/server";
 import * as acorn from "acorn";
 
 import { bindCurrentSubjectAccount, currentSubjectStorageKey, LAST_SUBJECT_ACCOUNT_KEY, readCurrentSubjectId, resetSubjectCatalogForTests } from "../src/lib/current-subject.ts";
-import { BOOT_ACCOUNT_PATH, BOOT_CHART_PROFILES_PATH, BOOT_MODELS_PATH, BOOT_READ_INIT, BOOT_READ_MAX_AGE_MS, BOOT_READS_GLOBAL, bootEarlyReadsScript, bootSessionsPath, clearBootReads, takeBootRead, takeBootSessionsRead, withBootFallback } from "../src/lib/boot-early-reads.ts";
+import { BOOT_ACCOUNT_PATH, BOOT_CHART_PROFILES_PATH, BOOT_MODELS_PATH, BOOT_READ_INIT, BOOT_READ_MAX_AGE_MS, BOOT_READS_GLOBAL, bootEarlyReadsScript, bootEarlyReadsScriptSrc, bootSessionsPath, clearBootReads, takeBootRead, takeBootSessionsRead, withBootFallback } from "../src/lib/boot-early-reads.ts";
 import { chinaLocations } from "../src/data/china-locations.ts";
 import { ensureChinaLocations, loadedChinaCountry, profileNeedsChinaLocations, resetChinaLocationsForTests } from "../src/lib/china-locations-client.ts";
 import { readProfile, selectedBirthPlace } from "../src/lib/home-profile.ts";
@@ -233,7 +233,13 @@ test("the early-read script is classic ES5 and only acts on / (T8)", () => {
     assert.deepEqual(runBootScript(path).sent, [], `${path} sends nothing`);
   }
   const layout = readFileSync(new URL("../src/app/layout.tsx", import.meta.url), "utf8");
-  assert.match(layout, /__html: bootEarlyReadsScript\(\)/);
+  // 原值：assert.match(layout, /__html: bootEarlyReadsScript\(\)/)（内联经典脚本）。
+  // 新值：<script async src={bootEarlyReadsScriptSrc()} />，src 是同一段脚本的 base64 data: URL。
+  // 原因：TASK-home-first-load-fix-20261001——内联脚本排在样式表之后，要等样式表下完才执行，线上早发推迟 2.4～3.1 s。
+  assert.match(layout, /<script async src=\{bootEarlyReadsScriptSrc\(\)\} \/>/);
+  const src = bootEarlyReadsScriptSrc();
+  assert.match(src, /^data:text\/javascript;base64,[A-Za-z0-9+/=]+$/);
+  assert.equal(Buffer.from(src.slice(src.indexOf(",") + 1), "base64").toString("utf8"), bootEarlyReadsScript(), "the data URL carries exactly the ES5 script");
 });
 
 test("the early reads are the normal requests, byte for byte (T8)", () => {