diff --git a/.vscode/settings.json b/.vscode/settings.json
index e02aef2..4ac9877 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,2 +1,67 @@
 {
-}
\ No newline at end of file
+  "window.title": "${activeEditorShort}${separator}${separator}deer-flow/frontend",
+  "todo-tree.regex.regex": "((%|#|//|<!--|\\{/\\*|^\\s*\\*)\\s*($TAGS)|^\\s*- \\[ \\])",
+  "todo-tree.general.tags": [
+    "TODO:",
+    "BUG:",
+    "TAG:",
+    "DONE:",
+    "MARK:",
+    "TEST:",
+    "XXX:"
+  ],
+  "todo-tree.regex.regexCaseSensitive": false,
+  "todo-tree.highlights.defaultHighlight": {
+    "foreground": "#000000",
+    "background": "#fff700",
+    "icon": "check",
+    "rulerColour": "#fff700",
+    "type": "tag",
+    "iconColour": "#fff700"
+  },
+  "todo-tree.highlights.customHighlight": {
+    "TODO:": {
+      "icon": "todo",
+      "background": "#fff700",
+      "rulerColour": "#fff700",
+      "iconColour": "#fff700"
+    },
+    "BUG:": {
+      "background": "#eb5c5c",
+      "icon": "bug",
+      "rulerColour": "#eb5c5c",
+      "iconColour": "#eb5c5c"
+    },
+    "TAG:": {
+      "background": "#38b2f4",
+      "icon": "tag",
+      "rulerColour": "#38b2f4",
+      "iconColour": "#38b2f4",
+      "rulerLane": "full"
+    },
+    "DONE:": {
+      "background": "#5eec95",
+      "icon": "check",
+      "rulerColour": "#5eec95",
+      "iconColour": "#5eec95"
+    },
+    "MARK:": {
+      "background": "#f90",
+      "icon": "note",
+      "rulerColour": "#f90",
+      "iconColour": "#f90"
+    },
+    "TEST:": {
+      "background": "#df7be6",
+      "icon": "flame",
+      "rulerColour": "#df7be6",
+      "iconColour": "#df7be6"
+    },
+    "XXX:": {
+      "background": "#d65d8e",
+      "icon": "versions",
+      "rulerColour": "#d65d8e",
+      "iconColour": "#d65d8e"
+    }
+  }
+}
diff --git a/js/api/api.js b/js/api/api.js
index 1ec2b40..3f02103 100644
--- a/js/api/api.js
+++ b/js/api/api.js
@@ -90,7 +90,7 @@ async function uploadToMistral(fileToProcess, mistralKey) {
  *
  * @param {File|Blob} fileToProcess - 需要上传的 File 或 Blob 对象。
  * @param {string} fileName - 文件名。
- * @returns {Promise<string>} 上传成功后返回 OSS 的公网访问 URL。
+ * @returns {Promise<{url: string, key: string}>} 上传成功后返回 OSS 的公网访问 URL 和 key。
  */
 async function uploadFileToOssViaProxy(fileToProcess, fileName) {
     const formData = new FormData();
@@ -115,7 +115,7 @@ async function uploadFileToOssViaProxy(fileToProcess, fileName) {
     if (!resultData || !resultData.url) {
         throw new Error('上传成功但未返回有效的URL');
     }
-    return resultData.url;
+    return { url: resultData.url, key: resultData.key };
 }
 
 /**
diff --git a/js/chatbot/actions/chatbot-actions.js b/js/chatbot/actions/chatbot-actions.js
index 43870fb..10104d1 100644
--- a/js/chatbot/actions/chatbot-actions.js
+++ b/js/chatbot/actions/chatbot-actions.js
@@ -110,8 +110,31 @@ window.ChatbotActions = {
 
       // 调用上传
       console.log('[handleProvidePdf] 开始上传到 OSS...');
-      const ossUrl = await window.uploadFileToOssViaProxy(pdfFileContent, `${currentDocName}`);
-      console.log('[handleProvidePdf] OSS 上传成功, URL:', ossUrl);
+      const { url: ossUrl, key: ossKey } = await window.uploadFileToOssViaProxy(pdfFileContent, `${currentDocName}`);
+      console.log('[handleProvidePdf] OSS 上传成功, URL:', ossUrl, 'Key:', ossKey);
+
+      // 保存 OSS URL 到数据库
+      if (window.storageAdapter && typeof window.storageAdapter.saveOssUrl === 'function') {
+        try {
+          await window.storageAdapter.saveOssUrl(dbDocId, ossUrl, ossKey);
+          console.log('[handleProvidePdf] OSS URL 已保存到数据库');
+        } catch (saveErr) {
+          console.warn('[handleProvidePdf] 保存 OSS URL 到数据库失败:', saveErr);
+        }
+      } else {
+        // 直接调用 API
+        try {
+          const apiUrl = (window.PBX_PROXY_BASE_URL || '/api') + `/documents/${dbDocId}/oss`;
+          await fetch(apiUrl, {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({ ossUrl, ossKey })
+          });
+          console.log('[handleProvidePdf] OSS URL 已通过 API 保存');
+        } catch (apiErr) {
+          console.warn('[handleProvidePdf] 通过 API 保存 OSS URL 失败:', apiErr);
+        }
+      }
 
       // 构建包含 file_url 的消息内容（智谱 AI 格式）
       const userMessageContent = [
diff --git a/js/history/history.js b/js/history/history.js
index ec0b76b..ecc5d6d 100644
--- a/js/history/history.js
+++ b/js/history/history.js
@@ -273,14 +273,24 @@ document.addEventListener('DOMContentLoaded', function() {
         if (historyClearMode === 'record') {
             if (pendingDeleteRecordId) {
                 removeFolderAssignmentForRecord(pendingDeleteRecordId);
-                await deleteResultFromDB(pendingDeleteRecordId);
+                // 使用 storageAdapter 删除（支持后端模式）
+                if (window.storageAdapter && typeof window.storageAdapter.deleteResultFromDB === 'function') {
+                    await window.storageAdapter.deleteResultFromDB(pendingDeleteRecordId);
+                } else if (typeof deleteResultFromDB === 'function') {
+                    await deleteResultFromDB(pendingDeleteRecordId);
+                }
                 await renderHistoryList();
                 if (typeof showNotification === 'function') {
                     showNotification('历史记录已删除。', 'success');
                 }
             }
         } else {
-            await clearAllResultsFromDB();
+            // 使用 storageAdapter 清空（支持后端模式）
+            if (window.storageAdapter && typeof window.storageAdapter.clearAllResultsFromDB === 'function') {
+                await window.storageAdapter.clearAllResultsFromDB();
+            } else if (typeof clearAllResultsFromDB === 'function') {
+                await clearAllResultsFromDB();
+            }
             clearFolderAssignments();
             historyUIState.activeFolder = 'all';
             historyUIState.searchQuery = '';
@@ -2194,7 +2204,12 @@ document.addEventListener('DOMContentLoaded', function() {
         const records = batchCache[batchId];
         if (!records || !records.length) return;
         for (const record of records) {
-            await deleteResultFromDB(record.id);
+            // 使用 storageAdapter 删除（支持后端模式）
+            if (window.storageAdapter && typeof window.storageAdapter.deleteResultFromDB === 'function') {
+                await window.storageAdapter.deleteResultFromDB(record.id);
+            } else if (typeof deleteResultFromDB === 'function') {
+                await deleteResultFromDB(record.id);
+            }
             removeFolderAssignmentForRecord(record.id);
         }
     }
diff --git a/js/history/history_detail_render.js b/js/history/history_detail_render.js
index 6378c89..43d5733 100644
--- a/js/history/history_detail_render.js
+++ b/js/history/history_detail_render.js
@@ -245,6 +245,30 @@ async function renderDetail() {
 
   const hasOriginalPdf = !!(meta.originalPdfBase64);
 
+  // ========== 将 PDF base64 转换为 File 对象，供 AI 助手的 PDF 功能使用 ==========
+  if (hasOriginalPdf && data.name) {
+    try {
+      // 使用 history_detail_scripts.js 中定义的 base64ToFile 函数
+      if (typeof base64ToFile === 'function') {
+        window.currentOriginalFile = base64ToFile(meta.originalPdfBase64, data.name);
+        console.log('[renderDetail] 已设置 window.currentOriginalFile，供 AI 助手使用');
+      } else {
+        // 如果 base64ToFile 不可用，手动转换
+        const base64Data = meta.originalPdfBase64;
+        const byteString = atob(base64Data);
+        const ab = new ArrayBuffer(byteString.length);
+        const ia = new Uint8Array(ab);
+        for (let i = 0; i < byteString.length; i++) {
+          ia[i] = byteString.charCodeAt(i);
+        }
+        window.currentOriginalFile = new File([ab], data.name, { type: 'application/pdf' });
+        console.log('[renderDetail] 已设置 window.currentOriginalFile（手动转换），供 AI 助手使用');
+      }
+    } catch (e) {
+      console.error('[renderDetail] 转换 PDF base64 为 File 失败:', e);
+    }
+  }
+
   console.log('[renderDetail] 检测结果:', {
     hasMinerUStructuredData,
     hasOriginalPdf,
diff --git a/js/storage/storage-adapter.js b/js/storage/storage-adapter.js
index c453b30..bef7059 100644
--- a/js/storage/storage-adapter.js
+++ b/js/storage/storage-adapter.js
@@ -25,6 +25,9 @@ let DEPLOYMENT_MODE = (getQueryModeOverride() || (window.ENV_DEPLOYMENT_MODE &&
 
 const API_BASE_URL = window.ENV_API_BASE_URL || '/api';
 
+// 后端认证状态（当 AUTH_DISABLED=true 时，前端也需要绕过认证检查）
+let backendAuthDisabled = false;
+
 async function autoDetectBackendAvailability(timeoutMs = 900) {
   // file:// 明确无后端
   if (window.location.protocol === 'file:') return false;
@@ -37,7 +40,20 @@ async function autoDetectBackendAvailability(timeoutMs = 900) {
     const id = setTimeout(() => controller.abort(), timeoutMs);
     const res = await fetch(`${API_BASE_URL}/health`, { signal: controller.signal, cache: 'no-store' });
     clearTimeout(id);
-    return res.ok;
+    if (res.ok) {
+      const data = await res.json();
+      // 如果后端禁用认证，设置假 token 并标记状态
+      // TODO: 生产环境必须移除此逻辑，强制要求用户登录认证
+      if (data.authDisabled) {
+        backendAuthDisabled = true;
+        // 设置假 token 让 AuthManager.isAuthenticated() 返回 true
+        if (!localStorage.getItem('auth_token')) {
+          localStorage.setItem('auth_token', 'dev-mode-no-auth');
+        }
+      }
+      return true;
+    }
+    return false;
   } catch {
     return false;
   }
@@ -253,6 +269,36 @@ class BackendStorage {
     }
   }
 
+  /**
+   * 保存 OSS URL 到文档（供 AI 助手使用）
+   * @param {string} id - 文档 ID
+   * @param {string} ossUrl - OSS 公网访问 URL
+   * @param {string} ossKey - OSS 对象 key（用于删除）
+   */
+  async saveOssUrl(id, ossUrl, ossKey) {
+    try {
+      if (!AuthManager.isAuthenticated()) {
+        // 前端模式：保存到 IndexedDB metadata
+        const doc = await this._fallbackTo('getResultFromDB', id);
+        if (doc) {
+          doc.metadata = doc.metadata || {};
+          doc.metadata.ossUrl = ossUrl;
+          doc.metadata.ossKey = ossKey;
+          await this._fallbackTo('saveResultToDB', doc);
+        }
+        return;
+      }
+      await this.fetchAPI(`/documents/${id}/oss`, {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ ossUrl, ossKey })
+      });
+    } catch (error) {
+      console.error('Failed to save OSS URL to document:', error);
+      throw error;
+    }
+  }
+
   async clearAllResultsFromDB() {
     try {
       if (!AuthManager.isAuthenticated()) {
@@ -477,6 +523,20 @@ class StorageAdapterFactory {
       getResultFromDB: window.getResultFromDB,
       deleteResultFromDB: window.deleteResultFromDB,
       clearAllResultsFromDB: window.clearAllResultsFromDB,
+      // OSS URL 保存（前端模式：保存到 IndexedDB metadata）
+      saveOssUrl: async function(id, ossUrl, ossKey) {
+        try {
+          const doc = await window.getResultFromDB(id);
+          if (doc) {
+            doc.metadata = doc.metadata || {};
+            doc.metadata.ossUrl = ossUrl;
+            doc.metadata.ossKey = ossKey;
+            await window.saveResultToDB(doc);
+          }
+        } catch (e) {
+          console.warn('[StorageAdapter] saveOssUrl failed in frontend mode:', e);
+        }
+      },
       loadGlossarySets: window.loadGlossarySets,
       saveGlossarySets: window.saveGlossarySets,
       saveAnnotationToDB: window.saveAnnotationToDB,
diff --git a/js/ui/immersive_layout_logic.js b/js/ui/immersive_layout_logic.js
index bc22c41..bc6703d 100644
--- a/js/ui/immersive_layout_logic.js
+++ b/js/ui/immersive_layout_logic.js
@@ -224,12 +224,12 @@
     // 检查是否为移动端设备
     if (window.innerWidth <= 700) {
       console.warn('拒绝在移动端（≤700px）进入沉浸式布局');
-      // 即使不进入沉浸模式，也需要显示页面
+      // 移动端：显示普通布局
       document.documentElement.classList.remove('immersive-pending');
       document.documentElement.classList.add('immersive-ready');
       document.body.classList.remove('immersive-pending');
       document.body.classList.add('immersive-ready');
-      return;
+      return true; // 移动端算作成功
     }
 
     reQueryDynamicElements();
@@ -256,12 +256,12 @@
       immersiveChatbotArea: !!immersiveChatbotArea
     });
 
+    // 【严格检查】如果元素缺失，返回 false 表示失败，不显示页面
+    // 调用者应该重试直到成功
     if (missingElements.length > 0) {
-      console.warn('Immersive mode elements not found:', missingElements.join(', '));
-      // 元素缺失时也需要显示页面
-      document.body.classList.remove('immersive-pending');
-      document.body.classList.add('immersive-ready');
-      return;
+      console.error('[enterImmersiveMode] 严重错误：沉浸模式元素缺失:', missingElements.join(', '));
+      console.error('[enterImmersiveMode] 拒绝显示普通布局，等待重试...');
+      return false; // 返回失败，不显示页面
     }
 
     isImmersiveActive = true;
@@ -430,6 +430,8 @@
     initializeTocDockResizer();
     localStorage.setItem(LS_IMMERSIVE_KEY, 'true');
     document.dispatchEvent(new CustomEvent('immersiveModeEntered'));
+
+    return true; // 成功进入沉浸模式
   }
   // 禁用退出沉浸模式功能 - 页面始终保持在沉浸式布局
   function exitImmersiveMode() {
@@ -513,8 +515,8 @@
 
   function mainInit() {
     if (!initializeDomElements()) {
-      console.warn('Immersive layout core static elements not found on DOMContentLoaded. Retrying shortly...');
-      setTimeout(mainInit, 500);
+      console.warn('[ImmersiveLayout] 核心静态元素未找到，200ms 后重试...');
+      setTimeout(mainInit, 200);
       return;
     }
 
@@ -534,25 +536,29 @@
     // }
     // window.addEventListener('resize', handleWindowResize);
 
-    // 强制始终进入沉浸模式（忽略 localStorage 状态）
-    // 页面默认沉浸式布局，且无法退出
-    const shouldEnterImmersive = true;
-
+    // 【严格沉浸模式】必须成功进入沉浸模式才显示页面
     console.log('[ImmersiveLayout] 强制进入沉浸模式');
 
-    // 检查是否为移动端，如果是则不进入沉浸模式
+    // 检查是否为移动端，如果是则显示普通布局
     if (window.innerWidth <= 700) {
-      console.log('检测到移动端设备，不进入沉浸式布局');
-      // 显示页面
+      console.log('[ImmersiveLayout] 检测到移动端设备，显示普通布局');
       document.documentElement.classList.remove('immersive-pending');
       document.documentElement.classList.add('immersive-ready');
       document.body.classList.remove('immersive-pending');
       document.body.classList.add('immersive-ready');
+      return;
+    }
+
+    // 尝试进入沉浸模式（静默模式，无动画）
+    const success = enterImmersiveMode({ silent: true });
+
+    if (success) {
+      console.log('[ImmersiveLayout] 成功进入沉浸模式');
     } else {
-      // 立即进入沉浸模式（静默模式，无动画）
-      console.log('[ImmersiveLayout] 准备进入沉浸模式, isImmersiveActive:', isImmersiveActive);
-      enterImmersiveMode({ silent: true });
-      console.log('[ImmersiveLayout] enterImmersiveMode 调用完成, isImmersiveActive:', isImmersiveActive);
+      // 失败时持续重试，不显示页面
+      console.error('[ImmersiveLayout] 进入沉浸模式失败，300ms 后重试...');
+      setTimeout(mainInit, 300);
+      return;
     }
 
     console.log('Immersive layout logic initialized.');
diff --git a/local-proxy/app.js b/local-proxy/app.js
index 56221c9..e927a27 100644
--- a/local-proxy/app.js
+++ b/local-proxy/app.js
@@ -63,12 +63,14 @@ app.get('/health', async (req, res) => {
     res.json({
       status: 'ok',
       database: 'connected',
+      authDisabled: process.env.AUTH_DISABLED === 'true',
       timestamp: Date.now()
     });
   } catch (error) {
     res.json({
       status: 'ok',
       database: 'disconnected',
+      authDisabled: process.env.AUTH_DISABLED === 'true',
       timestamp: Date.now()
     });
   }
diff --git a/local-proxy/auth/middleware.js b/local-proxy/auth/middleware.js
index 6024493..288d9a6 100644
--- a/local-proxy/auth/middleware.js
+++ b/local-proxy/auth/middleware.js
@@ -7,6 +7,7 @@ import fetch from 'node-fetch';
 import { prisma } from '../db/client.js';
 
 // 是否禁用认证（开发/测试模式）
+// TODO: 生产环境必须移除此配置，强制要求认证
 const AUTH_DISABLED = process.env.AUTH_DISABLED === 'true' || process.env.NODE_ENV === 'test';
 
 // 默认认证 API URL
@@ -17,6 +18,7 @@ const tokenCache = new Map();
 const CACHE_TTL = 5 * 60 * 1000; // 5 分钟
 
 // 测试用户（认证禁用时使用）
+// TODO: 生产环境必须移除此测试用户
 const TEST_USER = {
   id: 'test-user-001',
   username: 'testuser',
@@ -114,6 +116,7 @@ export async function ensureUserExists(userId, name) {
  */
 export async function requireAuth(req, res, next) {
   // 认证禁用模式（开发/测试）
+  // TODO: 生产环境必须移除此分支，强制要求认证
   if (AUTH_DISABLED) {
     await ensureUserExists(TEST_USER.id, TEST_USER.nickname);
     req.user = TEST_USER;
diff --git a/local-proxy/package.json b/local-proxy/package.json
index cff8066..86b6967 100644
--- a/local-proxy/package.json
+++ b/local-proxy/package.json
@@ -6,7 +6,10 @@
   "type": "module",
   "scripts": {
     "start": "node server.js",
-    "dev": "node --watch server.js"
+    "dev": "node --watch server.js",
+    "prisma:migrate": "npx prisma migrate dev",
+    "prisma:generate": "npx prisma generate",
+    "prisma:studio": "npx prisma studio"
   },
   "keywords": [
     "paper-burner",
diff --git a/local-proxy/prisma/migrations/20260325035303_/migration.sql b/local-proxy/prisma/migrations/20260325035303_/migration.sql
new file mode 100644
index 0000000..18a0dbd
--- /dev/null
+++ b/local-proxy/prisma/migrations/20260325035303_/migration.sql
@@ -0,0 +1,3 @@
+-- AlterTable
+ALTER TABLE "documents" ADD COLUMN     "ossKey" TEXT,
+ADD COLUMN     "ossUrl" TEXT;
diff --git a/local-proxy/prisma/schema.prisma b/local-proxy/prisma/schema.prisma
index 6ee3bbb..6900877 100644
--- a/local-proxy/prisma/schema.prisma
+++ b/local-proxy/prisma/schema.prisma
@@ -141,6 +141,10 @@ model Document {
   fileType String
   filePath String? // 如果启用文件上传存储
 
+  // OSS 存储（供 AI 助手使用）
+  ossUrl String? // OSS 公网访问 URL
+  ossKey String? // OSS 对象 key（用于删除）
+
   // 处理状态
   status DocStatus @default(PENDING)
 
diff --git a/local-proxy/routes/documents.js b/local-proxy/routes/documents.js
index 6085cc4..51648ba 100644
--- a/local-proxy/routes/documents.js
+++ b/local-proxy/routes/documents.js
@@ -5,9 +5,54 @@
 
 import express from 'express';
 import { prisma } from '../db/client.js';
+import OSS from 'ali-oss';
 
 const router = express.Router();
 
+// ==================== OSS 客户端初始化 ====================
+let ossClient = null;
+
+function initOssClient() {
+  const region = process.env.OSS_REGION;
+  const accessKeyId = process.env.OSS_ACCESS_KEY_ID;
+  const accessKeySecret = process.env.OSS_ACCESS_KEY_SECRET;
+  const bucket = process.env.OSS_BUCKET || process.env.OSS_BUCKET_NAME;
+
+  if (region && accessKeyId && accessKeySecret && bucket) {
+    let normalizedRegion = region;
+    if (!region.startsWith('oss-')) {
+      normalizedRegion = `oss-${region}`;
+    }
+    ossClient = new OSS({
+      region: normalizedRegion,
+      accessKeyId,
+      accessKeySecret,
+      bucket,
+      secure: true
+    });
+    console.log(`[Documents] OSS client initialized with bucket: ${bucket}`);
+  }
+}
+initOssClient();
+
+/**
+ * 删除 OSS 文件
+ * @param {string} ossKey - OSS 对象 key
+ * @returns {Promise<boolean>}
+ */
+async function deleteOssFile(ossKey) {
+  if (!ossClient || !ossKey) return false;
+
+  try {
+    await ossClient.delete(ossKey);
+    console.log(`[OSS] Deleted file: ${ossKey}`);
+    return true;
+  } catch (error) {
+    console.error(`[OSS] Failed to delete file ${ossKey}:`, error.message);
+    return false;
+  }
+}
+
 // 允许的状态值白名单
 const ALLOWED_STATUSES = ['PENDING', 'PROCESSING', 'COMPLETED', 'FAILED'];
 
@@ -313,6 +358,11 @@ router.delete('/:id', async (req, res, next) => {
     });
 
     if (document) {
+      // 删除 OSS 文件（如果有）
+      if (document.ossKey) {
+        await deleteOssFile(document.ossKey);
+      }
+
       await prisma.document.delete({
         where: { id }
       });
@@ -324,6 +374,40 @@ router.delete('/:id', async (req, res, next) => {
   }
 });
 
+// 保存 OSS URL 到文档（供 AI 助手使用）
+router.post('/:id/oss', async (req, res, next) => {
+  try {
+    const { id } = req.params;
+    const { ossUrl, ossKey } = req.body;
+
+    if (!ossUrl) {
+      return res.status(400).json({ error: 'ossUrl is required' });
+    }
+
+    // 验证文档所有权
+    const document = await prisma.document.findFirst({
+      where: {
+        id,
+        userId: req.user.id
+      }
+    });
+
+    if (!document) {
+      return res.status(404).json({ error: 'Document not found' });
+    }
+
+    // 更新文档的 OSS 信息
+    await prisma.document.update({
+      where: { id },
+      data: { ossUrl, ossKey }
+    });
+
+    res.json({ success: true, ossUrl, ossKey });
+  } catch (error) {
+    next(error);
+  }
+});
+
 // ==================== 标注管理 ====================
 
 // 保存标注
diff --git a/local-proxy/server.js b/local-proxy/server.js
index 97ece1a..54b2a12 100644
--- a/local-proxy/server.js
+++ b/local-proxy/server.js
@@ -820,6 +820,7 @@ async function handleOssUpload(req, res, origin) {
     jsonResponse(res, {
       success: true,
       url: urlToReturn,
+      key: objectName,  // 返回 ossKey 用于后续删除
       file_name: filePart.filename
     }, 200, origin);
 
diff --git a/views/history/history_detail.html b/views/history/history_detail.html
index 962dcf0..62eec76 100644
--- a/views/history/history_detail.html
+++ b/views/history/history_detail.html
@@ -97,6 +97,37 @@
         opacity: 1;
         transition: opacity 0.2s ease;
       }
+
+      /* 严格沉浸模式：默认隐藏普通布局 */
+      body.immersive-pending .app-shell {
+        display: none !important;
+      }
+
+      /* 只有沉浸模式激活后才显示内容 */
+      body:not(.immersive-active) .app-shell {
+        display: none !important;
+      }
+
+      /* 沉浸模式容器默认隐藏，由 JS 控制 */
+      #immersive-layout-container {
+        display: none !important;
+      }
+
+      /* 沉浸模式激活后显示容器 */
+      body.immersive-active #immersive-layout-container {
+        display: flex !important;
+      }
+
+      /* 移动端例外：显示普通布局 */
+      @media (max-width: 700px) {
+        body.immersive-pending .app-shell,
+        body:not(.immersive-active) .app-shell {
+          display: flex !important;
+        }
+        body.immersive-ready .app-shell {
+          display: flex !important;
+        }
+      }
     </style>
     <script>
       // 在 DOM 解析前就添加类，避免闪烁