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diff --git a/assets/js/offline-unpack.js b/assets/js/offline-unpack.js
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+/*
+ * Mayx的博客 · 离线模式核心逻辑（/offline.html 控制页使用，ES module）
+ *
+ * - activateOffline()：注册 SW，下载站点压缩包 /MayxBlog.7z，经 libarchive(WASM)
+ *   流式解包，把每个文件按站点路径写入 Cache Storage，最后写入就绪标记
+ *   （清单 + payloadSize 版本号），自此进入离线模式。
+ * - ensureFresh()：HEAD 探测线上压缩包大小，与标记中的 payloadSize 不一致
+ *   说明站点已更新 → 清空缓存，回退在线模式。
+ * - deactivateOffline()：清空缓存，手动切回在线模式。
+ * - readStatus()：读取当前离线状态，供控制页展示。
+ *
+ */
+
+const ARCHIVE_URL = '/MayxBlog.7z';
+const ARCHIVE_ROOT = 'blog/';
+const CACHE_NAME = 'mayxblog-offline-v1';
+const READY_KEY = '/__offline_manifest__';
+const WORKER_URL = '/vendor/libarchive/worker-bundle.js';
+
+const MIME = {
+  html: 'text/html; charset=utf-8',
+  htm: 'text/html; charset=utf-8',
+  css: 'text/css; charset=utf-8',
+  js: 'application/javascript; charset=utf-8',
+  mjs: 'application/javascript; charset=utf-8',
+  json: 'application/json; charset=utf-8',
+  xml: 'application/xml; charset=utf-8',
+  xsl: 'text/xsl; charset=utf-8',
+  opml: 'text/x-opml; charset=utf-8',
+  txt: 'text/plain; charset=utf-8',
+  md: 'text/markdown; charset=utf-8',
+  csv: 'text/csv; charset=utf-8',
+  svg: 'image/svg+xml',
+  png: 'image/png',
+  jpg: 'image/jpeg',
+  jpeg: 'image/jpeg',
+  gif: 'image/gif',
+  webp: 'image/webp',
+  avif: 'image/avif',
+  ico: 'image/x-icon',
+  bmp: 'image/bmp',
+  woff: 'font/woff',
+  woff2: 'font/woff2',
+  ttf: 'font/ttf',
+  otf: 'font/otf',
+  eot: 'application/vnd.ms-fontobject',
+  mp3: 'audio/mpeg',
+  mp4: 'video/mp4',
+  webm: 'video/webm',
+  '7z': 'application/x-7z-compressed',
+  zip: 'application/zip',
+  wasm: 'application/wasm',
+  mtn: 'application/octet-stream',
+  moc: 'application/octet-stream',
+  pdf: 'application/pdf',
+};
+
+function mimeFor(pathname) {
+  const dot = pathname.lastIndexOf('.');
+  const ext = dot === -1 ? '' : pathname.slice(dot + 1).toLowerCase();
+  return MIME[ext] || 'application/octet-stream';
+}
+
+function sitePathFor(entryPath) {
+  const normalized = entryPath.replace(/\\/g, '/');
+  if (!normalized.startsWith(ARCHIVE_ROOT)) return null;
+  const relative = normalized.slice(ARCHIVE_ROOT.length);
+  if (!relative) return null;
+
+  const segments = [];
+  for (const segment of relative.split('/')) {
+    if (!segment || segment === '.') continue;
+    if (segment === '..') return null;
+    segments.push(segment);
+  }
+  if (!segments.length) return null;
+  return '/' + segments.join('/');
+}
+
+/*
+ * 在独立 worker 中打开一层压缩包并流式吐出条目；
+ * 返回其中根级嵌套压缩包（下一层包装）的原始字节。
+ */
+function extractLayer(file, onEntry) {
+  return new Promise((resolve, reject) => {
+    const worker = new Worker(WORKER_URL);
+    const nested = [];
+    let settled = false;
+
+    const finish = (error) => {
+      if (settled) return;
+      settled = true;
+      worker.terminate();
+      if (error) reject(error);
+      else resolve(nested);
+    };
+
+    worker.addEventListener('error', (event) => {
+      finish(new Error(event.message || 'libarchive worker failed'));
+    });
+
+    worker.addEventListener('message', ({ data }) => {
+      if (data.type === 'ERROR') {
+        finish(new Error(data.error && data.error.message ? data.error.message : 'libarchive failed'));
+        return;
+      }
+      if (data.type === 'READY') {
+        worker.postMessage({ type: 'OPEN', file });
+        return;
+      }
+      if (data.type === 'OPENED') {
+        worker.postMessage({ type: 'EXTRACT_FILES' });
+        return;
+      }
+      if (data.type === 'END') {
+        finish(null);
+        return;
+      }
+      if (data.type !== 'ENTRY') return;
+
+      const entry = data.entry;
+      if (entry.type !== 'FILE' || !entry.fileData) return;
+
+      // 根级压缩包是下一层包装，不是站点内容
+      if (entry.path.replace(/\\/g, '/') === 'MayxBlog.7z') {
+        nested.push(entry.fileData);
+        return;
+      }
+      onEntry(entry);
+    });
+  });
+}
+
+/* 几十 MB 的缓存是浏览器常见的回收对象，而重新解包代价高，尽量申请持久存储。 */
+async function requestPersistence() {
+  if (!navigator.storage || !navigator.storage.persist) return false;
+  try {
+    if (await navigator.storage.persisted()) return true;
+    return await navigator.storage.persist();
+  } catch {
+    return false;
+  }
+}
+
+/* 读取就绪标记（= 离线模式状态）；损坏或缺清单的标记视为不存在。 */
+export async function readStatus() {
+  const cache = await caches.open(CACHE_NAME);
+  const hit = await cache.match(READY_KEY);
+  if (!hit) return null;
+  const meta = await hit.json().catch(() => null);
+  if (!meta || !Array.isArray(meta.keys) || !meta.keys.length) return null;
+  return meta;
+}
+
+/*
+ * 线上压缩包的大小即版本号。HEAD 不被 SW 拦截，拿到的一定是线上真实值；
+ * 网络失败返回 null，调用方选择信任现有缓存而不是误伤。
+ */
+async function payloadSize() {
+  try {
+    const response = await fetch(ARCHIVE_URL, { method: 'HEAD', cache: 'no-store' });
+    if (!response.ok) return null;
+    const size = Number(response.headers.get('content-length'));
+    return Number.isFinite(size) && size > 0 ? size : null;
+  } catch {
+    return null;
+  }
+}
+
+/*
+ * 控制页打开时调用：未启用 → {ready:false}；已启用且版本一致 → {ready:true, meta}；
+ * 版本不一致 → 清空缓存并返回 {ready:false, stale:true}（已回退在线模式）。
+ */
+export async function ensureFresh() {
+  const cache = await caches.open(CACHE_NAME);
+  const size = await payloadSize();
+  const meta = await readStatus();
+
+  if (!meta) return { ready: false, size, stale: false };
+  if (size && meta.payloadSize !== size) {
+    await caches.delete(CACHE_NAME);
+    return { ready: false, size, stale: true };
+  }
+  return { ready: true, size, stale: false, meta };
+}
+
+/*
+ * 启用离线模式：注册 SW → 清空旧缓存（同时清掉上次中断的残留，保证随后
+ * 的压缩包下载不会被旧缓存喂旧的 quine 副本）→ 下载并逐层解包 → 写标记。
+ */
+export async function activateOffline({ onProgress } = {}) {
+  if (!('serviceWorker' in navigator)) {
+    throw new Error('当前浏览器不支持 Service Worker，无法启用离线模式。');
+  }
+  await navigator.serviceWorker.register('/sw.js', { scope: '/' });
+  await navigator.serviceWorker.ready;
+  await caches.delete(CACHE_NAME);
+
+  const persisted = await requestPersistence();
+
+  // 写操作串行链，保证按到达顺序落盘且不产生无界并发
+  const cache = await caches.open(CACHE_NAME);
+  let writes = Promise.resolve();
+  const keys = new Set();
+  let files = 0;
+  let bytes = 0;
+  let skipped = 0;
+
+  const response = await fetch(ARCHIVE_URL, { cache: 'no-store' });
+  if (!response.ok) throw new Error(`无法下载站点压缩包：HTTP ${response.status}`);
+  const outer = await response.arrayBuffer();
+  const downloadedBytes = outer.byteLength;
+
+  let layer = [outer];
+  while (layer.length) {
+    const bytesThisLayer = layer.shift();
+    const file = new File([bytesThisLayer], 'MayxBlog.7z');
+
+    layer = await extractLayer(file, (entry) => {
+      const key = sitePathFor(entry.path);
+      if (!key) {
+        skipped += 1;
+        return;
+      }
+      const body = entry.fileData;
+      files += 1;
+      bytes += body.byteLength;
+
+      writes = writes.then(async () => {
+        await cache.put(key, new Response(body, {
+          status: 200,
+          headers: { 'Content-Type': mimeFor(key) },
+        }));
+        keys.add(key);
+      });
+
+      if (onProgress) onProgress({ done: false, files, bytes, skipped });
+    });
+  }
+
+  await writes;
+
+  const meta = {
+    files,
+    bytes,
+    skipped,
+    persisted,
+    payloadSize: downloadedBytes,
+    failed: files - keys.size,
+    keys: [...keys],
+    unpackedAt: new Date().toISOString(),
+  };
+  await cache.put(
+    READY_KEY,
+    new Response(JSON.stringify(meta), {
+      headers: { 'Content-Type': 'application/json; charset=utf-8' },
+    })
+  );
+
+  if (onProgress) onProgress({ done: true, cached: false, ...meta });
+  return meta;
+}
+
+/* 切回在线模式：删掉缓存（含标记），SW 随即恢复纯转发。返回之前是否处于离线模式。 */
+export async function deactivateOffline() {
+  const had = await readStatus();
+  await caches.delete(CACHE_NAME);
+  return Boolean(had);
+}