Lock phone UI to portrait with PWA and landscape gate.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/main.tsx

@@ -3,9 +3,11 @@ import { createRoot } from "react-dom/client";
 import { BrowserRouter } from "react-router-dom";
 import App from "./App";
 import { registerServiceWorker } from "./pwa/install";
+import { initPortraitLock } from "./pwa/portraitLock";
 import "./styles/app.css";
 
 registerServiceWorker();
+initPortraitLock();
 
 createRoot(document.getElementById("root")!).render(
   <StrictMode>

frontend/src/pwa/portraitLock.ts

@@ -0,0 +1,75 @@
+/** 手机端尽量锁定竖屏；浏览器页用遮罩提示，已安装 PWA 由 manifest 约束。 */
+
+type OrientationLockType =
+  | "any"
+  | "natural"
+  | "landscape"
+  | "portrait"
+  | "portrait-primary"
+  | "portrait-secondary"
+  | "landscape-primary"
+  | "landscape-secondary";
+
+function isPhoneLike(): boolean {
+  if (typeof window === "undefined") return false;
+  const coarse = window.matchMedia("(pointer: coarse)").matches;
+  const narrow = Math.min(window.screen.width, window.screen.height) <= 520;
+  const ua = navigator.userAgent || "";
+  const phoneUa = /Android.+Mobile|iPhone|iPod|Windows Phone/i.test(ua);
+  return phoneUa || (coarse && narrow);
+}
+
+async function tryLockPortrait(): Promise<void> {
+  const orient = screen.orientation as ScreenOrientation & {
+    lock?: (orientation: OrientationLockType) => Promise<void>;
+  };
+  if (!orient?.lock) return;
+  try {
+    await orient.lock("portrait");
+  } catch {
+    try {
+      await orient.lock("portrait-primary");
+    } catch {
+      /* 多数浏览器仅全屏/PWA 允许 lock，失败则靠遮罩 */
+    }
+  }
+}
+
+function ensureGate(): HTMLElement {
+  let el = document.getElementById("portrait-lock-gate");
+  if (el) return el;
+  el = document.createElement("div");
+  el.id = "portrait-lock-gate";
+  el.className = "portrait-lock-gate";
+  el.setAttribute("aria-live", "polite");
+  el.innerHTML =
+    '<div class="portrait-lock-card">' +
+    '<p class="portrait-lock-title">请竖屏使用</p>' +
+    '<p class="portrait-lock-sub">手机端仅支持竖屏浏览</p>' +
+    "</div>";
+  document.body.appendChild(el);
+  return el;
+}
+
+function syncGate(): void {
+  if (!isPhoneLike()) {
+    const el = document.getElementById("portrait-lock-gate");
+    if (el) el.classList.remove("show");
+    return;
+  }
+  const landscape = window.matchMedia("(orientation: landscape)").matches;
+  ensureGate().classList.toggle("show", landscape);
+  if (!landscape) void tryLockPortrait();
+}
+
+/** 注册竖屏锁定与横屏提示遮罩。 */
+export function initPortraitLock(): void {
+  if (typeof window === "undefined") return;
+  syncGate();
+  window.addEventListener("orientationchange", syncGate);
+  window.addEventListener("resize", syncGate);
+  document.addEventListener("visibilitychange", () => {
+    if (document.visibilityState === "visible") syncGate();
+  });
+  void tryLockPortrait();
+}

frontend/src/styles/app.css

@@ -33,6 +33,39 @@ body {
     var(--bg);
 }
 
+.portrait-lock-gate {
+  display: none;
+  position: fixed;
+  inset: 0;
+  z-index: 9999;
+  align-items: center;
+  justify-content: center;
+  padding: 24px;
+  background: rgba(11, 14, 17, 0.96);
+  text-align: center;
+}
+
+.portrait-lock-gate.show {
+  display: flex;
+}
+
+.portrait-lock-card {
+  max-width: 280px;
+}
+
+.portrait-lock-title {
+  margin: 0 0 8px;
+  font-size: 20px;
+  font-weight: 700;
+  color: var(--accent);
+}
+
+.portrait-lock-sub {
+  margin: 0;
+  font-size: 14px;
+  color: var(--muted);
+}
+
 button,
 input {
   font: inherit;