diff --git a/static/app.js b/static/app.js
index 62483d8..a9f420e 100644
--- a/static/app.js
+++ b/static/app.js
@@ -1,32 +1,37 @@
 /**
  * LLM 论文图书馆 — 前端 JS
- * 页面加载检测 arXiv/HF 连通性 → 底部状态条
- * 点击论文：arXiv 连通? → iframe 直连 arXiv → 5s 超时 → HK 兜底
- * IDM 拦就拦，不额外对抗
+ * 打开时 ping 所有论文源 → 底部状态条 → 点击论文直用缓存结果
  */
 
 const API = '/api';
 
 let modules = {};
 let moduleData = {};
+let currentPdf = null;
 let pdfTimeout = null;
-let networkStatus = {};
+let networkStatus = {}; // { arxiv: bool, huggingface: bool, hk: bool }
 
-const $  = (sel) => document.querySelector(sel);
+const $ = (sel) => document.querySelector(sel);
 const $$ = (sel) => document.querySelectorAll(sel);
 const TAG_CLASS = { '起点':'tag-start','关键节点':'tag-milestone','前沿':'tag-frontier','前瞻':'tag-forward','支线':'tag-branch' };
 
-// ══════════════════ INIT ═══════════════════════════════
+// ═══════════════ INIT ═══════════════════════════════════
 async function init() {
+  // Build network status bar
   buildStatusBar();
+  // Load modules
   try {
     const resp = await fetch(`${API}/modules`);
     const mods = await resp.json();
+    modules = {};
     for (const m of mods) modules[m.id] = m;
     renderCards(mods);
     attachGlowTracking();
   } catch (e) { console.error(e); }
+
+  // Ping sources
   checkSources();
+
   document.addEventListener('keydown', e => {
     if (e.key === 'Escape') {
       if ($('#pdfOverlay')?.classList.contains('open')) closePdf();
@@ -35,31 +40,37 @@ async function init() {
   });
 }
 
-// ══════════════════ STATUS BAR ════════════════════════
+// ═══════════════ STATUS BAR ════════════════════════════
 function buildStatusBar() {
   const bar = document.createElement('div');
-  bar.id = 'statusBar'; bar.className = 'status-bar';
-  bar.innerHTML = `<span class="status-label">连通性检测</span>
+  bar.id = 'statusBar';
+  bar.className = 'status-bar';
+  bar.innerHTML = `
+    <span class="status-label">连通性检测</span>
     <span class="status-item" id="status-arxiv"><span class="status-dot"></span> arXiv <span class="status-ms" id="ms-arxiv">—</span></span>
-    <span class="status-item" id="status-hf"><span class="status-dot"></span> HuggingFace <span class="status-ms" id="ms-hf">—</span></span>`;
+    <span class="status-item" id="status-hf"><span class="status-dot"></span> HuggingFace <span class="status-ms" id="ms-hf">—</span></span>
+  `;
   document.body.appendChild(bar);
 }
 
 function setStatus(id, ok, ms, aborted) {
   networkStatus[id.replace('status-','')] = ok;
-  const el = document.getElementById(id); if (!el) return;
-  el.querySelector('.status-dot').className = 'status-dot ' + (ok ? 'status-ok' : 'status-fail');
-  const msEl = document.getElementById('ms-'+id.replace('status-',''));
+  const el = document.getElementById(id);
+  if (!el) return;
+  const dot = el.querySelector('.status-dot');
+  dot.className = 'status-dot ' + (ok ? 'status-ok' : 'status-fail');
+  const msEl = document.getElementById('ms-' + id.replace('status-',''));
   if (msEl) {
-    if (aborted) msEl.textContent = '超时';
-    else if (ok) msEl.textContent = ms+'ms';
-    else          msEl.textContent = '—';
+    if (aborted) msEl.textContent = '超时 (4s)';
+    else if (ok) msEl.textContent = ms + 'ms';
+    else           msEl.textContent = '—';
   }
 }
 
 async function checkSource(name, url, statusId) {
   const start = performance.now();
   let aborted = false;
+  // Add cache-buster and force no-store to avoid browser caching
   const probeUrl = url + '?_=' + Date.now();
   try {
     const ctrl = new AbortController();
@@ -73,26 +84,26 @@ async function checkSource(name, url, statusId) {
   }
 }
 
-function checkSources() {
+async function checkSources() {
   checkSource('arxiv', 'https://arxiv.org/favicon.ico', 'status-arxiv');
-  checkSource('hf',   'https://huggingface.co/favicon.ico', 'status-hf');
+  checkSource('hf', 'https://huggingface.co/favicon.ico', 'status-hf');
 }
 
-// ══════════════════ GLOW ══════════════════════════════
+// ═══════════════ GLOW ══════════════════════════════════
 function attachGlowTracking() {
   $$('.card').forEach(card => {
     card.addEventListener('mousemove', e => {
-      const r = card.getBoundingClientRect();
-      card.style.setProperty('--mx', (e.clientX-r.left)/r.width*100+'%');
-      card.style.setProperty('--my', (e.clientY-r.top)/r.height*100+'%');
+      const rect = card.getBoundingClientRect();
+      card.style.setProperty('--mx', ((e.clientX - rect.left) / rect.width * 100) + '%');
+      card.style.setProperty('--my', ((e.clientY - rect.top) / rect.height * 100) + '%');
     });
   });
 }
 
-// ══════════════════ CARDS → MODAL → PAPERS ═══════════
+// ═══════════════ CARDS -> MODAL -> PAPERS ═══════════════
 function renderCards(mods) {
-  $('#moduleGrid').innerHTML = mods.map(m =>
-    `<div class="card card-${m.id}" onclick="openModule('${m.id}')">
+  $('#moduleGrid').innerHTML = mods.map(m => `
+    <div class="card card-${m.id}" onclick="openModule('${m.id}')">
       <div class="card-header"><span class="card-icon">${m.icon}</span> ${m.name}</div>
       <div class="card-desc">${m.desc}</div>
       <div class="card-badge">${m.area_count} 子领域 · ${m.paper_count} 篇</div>
@@ -102,43 +113,45 @@ function renderCards(mods) {
 async function openModule(modId) {
   let data = moduleData[modId];
   if (!data) {
-    try { data = await (await fetch(`${API}/modules/${modId}`)).json(); moduleData[modId]=data; }
-    catch { return; }
+    try { data = await (await fetch(`${API}/modules/${modId}`)).json(); moduleData[modId] = data; }
+    catch (e) { return; }
   }
   const mod = modules[modId];
   $('#modalTitle').innerHTML = `<span class="card-icon">${mod?.icon||''}</span> ${data.name}`;
-  $('#modalSubtitle').textContent = data.desc||'';
-  const areas = data.areas||[];
-  $('#modalTabs').innerHTML = areas.map((a,i)=>`<button class="tab ${i?'':'active'}" onclick="switchArea(${i})">${a.name}</button>`).join('');
-  if (areas.length) { $('#modalTabs').dataset.areaIdx='0'; renderPapers(areas[0]); }
+  $('#modalSubtitle').textContent = data.desc || '';
+  const areas = data.areas || [];
+  $('#modalTabs').innerHTML = areas.map((a,i) =>
+    `<button class="tab ${i===0?'active':''}" onclick="switchArea(${i})">${a.name}</button>`).join('');
+  if (areas.length > 0) { $('#modalTabs').dataset.areaIdx = '0'; renderPapers(areas[0]); }
   $('#overlay').classList.add('open');
 }
 
 function switchArea(idx) {
   const data = Object.values(moduleData).find(d => d.areas && d.areas[idx]);
   if (!data) return;
-  $$('#modalTabs .tab').forEach((t,i)=>t.classList.toggle('active',i===idx));
+  $$('#modalTabs .tab').forEach((t,i) => t.classList.toggle('active', i===idx));
   renderPapers(data.areas[idx]);
 }
 
 function closeModal() { $('#overlay').classList.remove('open'); }
 
 function renderPapers(area) {
-  const s = (l, ps, c) => ps.length ? `<div class="section-label ${c}">${l}</div>`+ps.map(renderPaper).join('') : '';
-  $('#modalContent').innerHTML =
-    s('📌 主线论文', area.mainline||[],'mainline') +
-    s('🌿 支线论文', area.branches||[],'branch') +
-    s('🔮 前瞻探索', area.forward||[],'forward') ||
-    '<p style="color:var(--text-dim);padding:20px;">暂无论文数据</p>';
+  let h = '';
+  function s(l, ps, c) { return ps.length ? `<div class="section-label ${c}">${l}</div>`+ps.map(renderPaper).join('') : ''; }
+  h += s('📌 主线论文', area.mainline||[], 'mainline');
+  h += s('🌿 支线论文', area.branches||[], 'branch');
+  h += s('🔮 前瞻探索', area.forward||[], 'forward');
+  $('#modalContent').innerHTML = h || '<p style="color:var(--text-dim);padding:20px;">暂无论文数据</p>';
 }
 
 function renderPaper(p) {
   const pdfUrl = getPdfLink(p);
-  const tags = (p.tags||[]).map(t=>`<span class="paper-tag ${TAG_CLASS[t]||'tag-branch'}">${t}</span>`).join(' ');
+  const id = 'p'+Math.random().toString(36).slice(2,8);
+  const tags = (p.tags||[]).map(t => `<span class="paper-tag ${TAG_CLASS[t]||'tag-branch'}">${t}</span>`).join(' ');
   const links = [];
   if (pdfUrl) links.push(`<button class="paper-link" data-pdf="${encodeURIComponent(pdfUrl)}" data-title="${encodeURIComponent(p.title)}" onclick="openPdfBtn(this)">📄 阅读</button>`);
   else if (p.arxiv) links.push(`<a class="paper-link" href="https://arxiv.org/abs/${p.arxiv}" target="_blank">📋 arXiv</a>`);
-  return `<div class="paper-item"><div class="paper-year">${p.year||'—'}</div><div class="paper-body">
+  return `<div class="paper-item"><div class="paper-year">${p.year||'—'}</div><div class="paper-body" id="${id}">
     <div class="paper-title">${p.title}</div>
     <div class="paper-meta"><span>${p.authors||''}</span>${p.venue?`<span class="paper-venue">${p.venue}</span>`:''}${tags}</div>
     <div class="paper-links">${links.join('')}</div>
@@ -146,91 +159,101 @@ function renderPaper(p) {
 }
 
 function getPdfLink(p) {
-  // 有 pdf 字段 → 返回外部源 URL（arxiv 直连 / HF 直连）
   if (p.pdf) return p.pdf;
-  // 只有 arxiv id → arXiv 直连
   if (p.arxiv) return `https://arxiv.org/pdf/${p.arxiv}.pdf`;
   return null;
 }
 
 function openPdfBtn(btn) { openPdf(btn.dataset.pdf, btn.dataset.title); }
 
-// ══════════════════ PDF VIEWER ════════════════════════
-function getLocalUrl(extUrl) {
-  // arXiv
+// ═══════════════ PDF VIEWER (状态条驱动) ═══════════════
+function getLocalPdfUrl(extUrl) {
   const am = extUrl.match(/arxiv\.org\/pdf\/(\d+\.\d+)/);
   if (am) return `/papers/arxiv/${am[1]}.pdf`;
-  // HuggingFace
-  if (extUrl.includes('huggingface.co')) {
-    const name = decodeURIComponent(extUrl).split('/').pop().replace('.pdf','');
-    return `/papers/hf/${name}.pdf`;
-  }
+  if (extUrl.includes('huggingface.co')) return `/papers/hf/${extUrl.split('/').pop().replace('.pdf','')}.pdf`;
   return null;
 }
 
 function openPdf(url, title) {
   const decodedUrl = decodeURIComponent(url);
   const decodedTitle = decodeURIComponent(title);
+  currentPdf = decodedUrl;
+  const hkFallback = getLocalPdfUrl(decodedUrl);
 
-  // 构建 overlay
   if (!$('#pdfOverlay')) {
     const div = document.createElement('div'); div.id='pdfOverlay'; div.className='pdf-overlay';
     div.innerHTML = `<div class="pdf-container" id="pdfContainer">
-      <div class="pdf-toolbar"><span id="pdfTitle">PDF</span><span id="pdfStatus" style="color:var(--orange);font-size:0.8em;margin-left:8px;"></span>
-        <button onclick="window.open($('#pdfFrame').src || currentPdf,'_blank')">🔗 新窗口</button>
+      <div class="pdf-toolbar"><span id="pdfTitle">PDF</span><span id="pdfStatus" style="color:var(--orange);font-size:0.8em;margin-left:8px;display:none"></span>
+        <button onclick="window.open(currentPdf,'_blank')">🔗 新窗口</button>
         <button class="pdf-close" onclick="closePdf()">&times;</button></div>
       <iframe class="pdf-frame" id="pdfFrame" src=""></iframe></div>`;
     document.body.appendChild(div);
     div.addEventListener('click', e => { if (e.target===div) closePdf(); });
   }
 
-  if (pdfTimeout) { clearTimeout(pdfTimeout); pdfTimeout=null; }
+  if (pdfTimeout) { clearTimeout(pdfTimeout); pdfTimeout = null; }
   $('#pdfTitle').textContent = decodedTitle;
-  $('#pdfStatus').textContent = '';
+  $('#pdfStatus').style.display = 'none';
   const frame = $('#pdfFrame');
   let loaded = false;
+  let abortCtrl = null;
   frame.src = 'about:blank';
-  frame.onload = ()=>{ loaded=true; if(pdfTimeout){clearTimeout(pdfTimeout);pdfTimeout=null;} $('#pdfStatus').textContent=''; };
 
-  const hkLocalUrl = getLocalUrl(decodedUrl);
+  frame.onload = () => {
+    loaded = true;
+    if (pdfTimeout) { clearTimeout(pdfTimeout); pdfTimeout = null; }
+    $('#pdfStatus').style.display = 'none';
+  };
+
   const isArxiv = decodedUrl.includes('arxiv.org');
-  const isHF = decodedUrl.includes('huggingface.co');
-  const isRemote = isArxiv || isHF;
-  const sourceOk = isArxiv ? networkStatus['arxiv'] !== false
-                : isHF     ? networkStatus['hf'] !== false
-                : false;
+  const remoteOk = (isArxiv && networkStatus['arxiv'] !== false);
 
-  // 弹框先出
-  $('#pdfOverlay').classList.add('open');
-
-  if (isRemote && sourceOk) {
-    // 远程源 iframe 直连
+  // arXiv: iframe 直连（跨域，IDM 只能认了）
+  if (remoteOk) {
     loaded = false;
-    $('#pdfStatus').textContent = isArxiv ? '🌐 arXiv 加载中...' : '🤗 HuggingFace 加载中...';
+    $('#pdfStatus').textContent = '🌐 arXiv 加载中...';
+    $('#pdfStatus').style.display = '';
+    frame.onload = () => { loaded=true; $('#pdfStatus').style.display='none'; };
     frame.src = decodedUrl;
 
-    pdfTimeout = setTimeout(() => {
+    pdfTimeout = setTimeout(async () => {
       if (loaded) return;
-      if (!hkLocalUrl) { $('#pdfStatus').textContent='⚠️ 超时'; return; }
-      $('#pdfStatus').textContent = '⏳ 超时，走 HK 服务器...';
-      frame.src = hkLocalUrl;
+      if (!hkFallback) { $('#pdfStatus').textContent='⚠️ arXiv 超时'; return; }
+      // fallback to HK, use fetch→blob to beat IDM
+      $('#pdfStatus').textContent = '⏳ arXiv 超时，走 HK 服务器...';
+      try {
+        const resp = await fetch(hkFallback, { cache:'default' });
+        const blobUrl = URL.createObjectURL(await resp.blob());
+        $('#pdfStatus').textContent = '';
+        frame.src = blobUrl;
+      } catch(e) { $('#pdfStatus').textContent = '⚠️ HK 加载失败'; }
     }, 5000);
   } else {
-    // 直接走 HK
-    $('#pdfStatus').textContent = hkLocalUrl ? '📂 HK 服务器加载中...' : '⏳ 加载中...';
-    frame.src = hkLocalUrl || decodedUrl;
+    // arXiv down / local / HF → use HK with fetch→blob
+    const src = hkFallback || decodedUrl;
+    $('#pdfStatus').textContent = hkFallback ? '📂 HK 服务器加载中...' : '⏳ 加载中...';
+    $('#pdfStatus').style.display = '';
+    try {
+      const resp = await fetch(src, { cache:'default' });
+      const blobUrl = URL.createObjectURL(await resp.blob());
+      $('#pdfStatus').textContent = '';
+      frame.src = blobUrl;
+    } catch(e) { $('#pdfStatus').textContent = '⚠️ 加载失败'; }
   }
+
+  $('#pdfOverlay').classList.add('open');
 }
 
 function closePdf() {
-  if (pdfTimeout) { clearTimeout(pdfTimeout); pdfTimeout=null; }
+  if (pdfTimeout) { clearTimeout(pdfTimeout); pdfTimeout = null; }
   $('#pdfOverlay').classList.remove('open');
   $('#pdfFrame').src = '';
+  currentPdf = null;
 }
 
-// ══════════════════ SEARCH ════════════════════════════
+// ═══════════════ SEARCH ═══════════════════════════════
 function searchPapers(q) {
-  q=(q||'').toLowerCase().trim();
+  q = (q||'').toLowerCase().trim();
   if (q.length<2) { $$('.card').forEach(c=>c.style.outline=''); return; }
   fetch(`${API}/papers?q=${encodeURIComponent(q)}&limit=10`).then(r=>r.json()).then(ps=>{
     const matched = new Set(ps.map(p=>p.module_id));
@@ -241,7 +264,7 @@ function searchPapers(q) {
   });
 }
 
-// ══════════════════ EVENTS ════════════════════════════
+// ═══════════════ EVENTS ═══════════════════════════════
 if (typeof document !== 'undefined') {
   document.addEventListener('DOMContentLoaded', () => {
     init();
diff --git a/static/index.html b/static/index.html
index e7132a2..364bafe 100644
--- a/static/index.html
+++ b/static/index.html
@@ -29,6 +29,283 @@
   </div>
 </div>
 
-<script src="/app.js"></script>
+<script>
+/**
+ * LLM 论文图书馆 — 前端 JS
+ * 打开时 ping 所有论文源 → 底部状态条 → 点击论文直用缓存结果
+ */
+
+const API = '/api';
+
+let modules = {};
+let moduleData = {};
+let currentPdf = null;
+let pdfTimeout = null;
+let networkStatus = {}; // { arxiv: bool, huggingface: bool, hk: bool }
+
+const $ = (sel) => document.querySelector(sel);
+const $$ = (sel) => document.querySelectorAll(sel);
+const TAG_CLASS = { '起点':'tag-start','关键节点':'tag-milestone','前沿':'tag-frontier','前瞻':'tag-forward','支线':'tag-branch' };
+
+// ═══════════════ INIT ═══════════════════════════════════
+async function init() {
+  // Build network status bar
+  buildStatusBar();
+  // Load modules
+  try {
+    const resp = await fetch(`${API}/modules`);
+    const mods = await resp.json();
+    modules = {};
+    for (const m of mods) modules[m.id] = m;
+    renderCards(mods);
+    attachGlowTracking();
+  } catch (e) { console.error(e); }
+
+  // Ping sources
+  checkSources();
+
+  document.addEventListener('keydown', e => {
+    if (e.key === 'Escape') {
+      if ($('#pdfOverlay')?.classList.contains('open')) closePdf();
+      else if ($('#overlay').classList.contains('open')) closeModal();
+    }
+  });
+}
+
+// ═══════════════ STATUS BAR ════════════════════════════
+function buildStatusBar() {
+  const bar = document.createElement('div');
+  bar.id = 'statusBar';
+  bar.className = 'status-bar';
+  bar.innerHTML = `
+    <span class="status-label">连通性检测</span>
+    <span class="status-item" id="status-arxiv"><span class="status-dot"></span> arXiv <span class="status-ms" id="ms-arxiv">—</span></span>
+    <span class="status-item" id="status-hf"><span class="status-dot"></span> HuggingFace <span class="status-ms" id="ms-hf">—</span></span>
+  `;
+  document.body.appendChild(bar);
+}
+
+function setStatus(id, ok, ms, aborted) {
+  networkStatus[id.replace('status-','')] = ok;
+  const el = document.getElementById(id);
+  if (!el) return;
+  const dot = el.querySelector('.status-dot');
+  dot.className = 'status-dot ' + (ok ? 'status-ok' : 'status-fail');
+  const msEl = document.getElementById('ms-' + id.replace('status-',''));
+  if (msEl) {
+    if (aborted) msEl.textContent = '超时 (4s)';
+    else if (ok) msEl.textContent = ms + 'ms';
+    else           msEl.textContent = '—';
+  }
+}
+
+async function checkSource(name, url, statusId) {
+  const start = performance.now();
+  let aborted = false;
+  // Add cache-buster and force no-store to avoid browser caching
+  const probeUrl = url + '?_=' + Date.now();
+  try {
+    const ctrl = new AbortController();
+    setTimeout(() => { aborted = true; ctrl.abort(); }, 4000);
+    await fetch(probeUrl, { mode: 'no-cors', signal: ctrl.signal, cache: 'no-store' });
+    const ms = Math.round(performance.now() - start);
+    setStatus(statusId, true, ms, false);
+  } catch {
+    const ms = Math.round(performance.now() - start);
+    setStatus(statusId, false, ms, aborted);
+  }
+}
+
+async function checkSources() {
+  checkSource('arxiv', 'https://arxiv.org/favicon.ico', 'status-arxiv');
+  checkSource('hf', 'https://huggingface.co/favicon.ico', 'status-hf');
+}
+
+// ═══════════════ GLOW ══════════════════════════════════
+function attachGlowTracking() {
+  $$('.card').forEach(card => {
+    card.addEventListener('mousemove', e => {
+      const rect = card.getBoundingClientRect();
+      card.style.setProperty('--mx', ((e.clientX - rect.left) / rect.width * 100) + '%');
+      card.style.setProperty('--my', ((e.clientY - rect.top) / rect.height * 100) + '%');
+    });
+  });
+}
+
+// ═══════════════ CARDS -> MODAL -> PAPERS ═══════════════
+function renderCards(mods) {
+  $('#moduleGrid').innerHTML = mods.map(m => `
+    <div class="card card-${m.id}" onclick="openModule('${m.id}')">
+      <div class="card-header"><span class="card-icon">${m.icon}</span> ${m.name}</div>
+      <div class="card-desc">${m.desc}</div>
+      <div class="card-badge">${m.area_count} 子领域 · ${m.paper_count} 篇</div>
+    </div>`).join('');
+}
+
+async function openModule(modId) {
+  let data = moduleData[modId];
+  if (!data) {
+    try { data = await (await fetch(`${API}/modules/${modId}`)).json(); moduleData[modId] = data; }
+    catch (e) { return; }
+  }
+  const mod = modules[modId];
+  $('#modalTitle').innerHTML = `<span class="card-icon">${mod?.icon||''}</span> ${data.name}`;
+  $('#modalSubtitle').textContent = data.desc || '';
+  const areas = data.areas || [];
+  $('#modalTabs').innerHTML = areas.map((a,i) =>
+    `<button class="tab ${i===0?'active':''}" onclick="switchArea(${i})">${a.name}</button>`).join('');
+  if (areas.length > 0) { $('#modalTabs').dataset.areaIdx = '0'; renderPapers(areas[0]); }
+  $('#overlay').classList.add('open');
+}
+
+function switchArea(idx) {
+  const data = Object.values(moduleData).find(d => d.areas && d.areas[idx]);
+  if (!data) return;
+  $$('#modalTabs .tab').forEach((t,i) => t.classList.toggle('active', i===idx));
+  renderPapers(data.areas[idx]);
+}
+
+function closeModal() { $('#overlay').classList.remove('open'); }
+
+function renderPapers(area) {
+  let h = '';
+  function s(l, ps, c) { return ps.length ? `<div class="section-label ${c}">${l}</div>`+ps.map(renderPaper).join('') : ''; }
+  h += s('📌 主线论文', area.mainline||[], 'mainline');
+  h += s('🌿 支线论文', area.branches||[], 'branch');
+  h += s('🔮 前瞻探索', area.forward||[], 'forward');
+  $('#modalContent').innerHTML = h || '<p style="color:var(--text-dim);padding:20px;">暂无论文数据</p>';
+}
+
+function renderPaper(p) {
+  const pdfUrl = getPdfLink(p);
+  const id = 'p'+Math.random().toString(36).slice(2,8);
+  const tags = (p.tags||[]).map(t => `<span class="paper-tag ${TAG_CLASS[t]||'tag-branch'}">${t}</span>`).join(' ');
+  const links = [];
+  if (pdfUrl) links.push(`<button class="paper-link" data-pdf="${encodeURIComponent(pdfUrl)}" data-title="${encodeURIComponent(p.title)}" onclick="openPdfBtn(this)">📄 阅读</button>`);
+  else if (p.arxiv) links.push(`<a class="paper-link" href="https://arxiv.org/abs/${p.arxiv}" target="_blank">📋 arXiv</a>`);
+  return `<div class="paper-item"><div class="paper-year">${p.year||'—'}</div><div class="paper-body" id="${id}">
+    <div class="paper-title">${p.title}</div>
+    <div class="paper-meta"><span>${p.authors||''}</span>${p.venue?`<span class="paper-venue">${p.venue}</span>`:''}${tags}</div>
+    <div class="paper-links">${links.join('')}</div>
+  </div></div>`;
+}
+
+function getPdfLink(p) {
+  if (p.pdf) return p.pdf;
+  if (p.arxiv) return `https://arxiv.org/pdf/${p.arxiv}.pdf`;
+  return null;
+}
+
+function openPdfBtn(btn) { openPdf(btn.dataset.pdf, btn.dataset.title); }
+
+// ═══════════════ PDF VIEWER (状态条驱动) ═══════════════
+function getLocalPdfUrl(extUrl) {
+  const am = extUrl.match(/arxiv\.org\/pdf\/(\d+\.\d+)/);
+  if (am) return `/papers/arxiv/${am[1]}.pdf`;
+  if (extUrl.includes('huggingface.co')) return `/papers/hf/${extUrl.split('/').pop().replace('.pdf','')}.pdf`;
+  return null;
+}
+
+function openPdf(url, title) {
+  const decodedUrl = decodeURIComponent(url);
+  const decodedTitle = decodeURIComponent(title);
+  currentPdf = decodedUrl;
+  const hkFallback = getLocalPdfUrl(decodedUrl);
+
+  if (!$('#pdfOverlay')) {
+    const div = document.createElement('div'); div.id='pdfOverlay'; div.className='pdf-overlay';
+    div.innerHTML = `<div class="pdf-container" id="pdfContainer">
+      <div class="pdf-toolbar"><span id="pdfTitle">PDF</span><span id="pdfStatus" style="color:var(--orange);font-size:0.8em;margin-left:8px;display:none"></span>
+        <button onclick="window.open(currentPdf,'_blank')">🔗 新窗口</button>
+        <button class="pdf-close" onclick="closePdf()">&times;</button></div>
+      <iframe class="pdf-frame" id="pdfFrame" src=""></iframe></div>`;
+    document.body.appendChild(div);
+    div.addEventListener('click', e => { if (e.target===div) closePdf(); });
+  }
+
+  if (pdfTimeout) { clearTimeout(pdfTimeout); pdfTimeout = null; }
+  $('#pdfTitle').textContent = decodedTitle;
+  $('#pdfStatus').style.display = 'none';
+  const frame = $('#pdfFrame');
+  let loaded = false;
+  let abortCtrl = null;
+  frame.src = 'about:blank';
+
+  frame.onload = () => {
+    loaded = true;
+    if (pdfTimeout) { clearTimeout(pdfTimeout); pdfTimeout = null; }
+    $('#pdfStatus').style.display = 'none';
+  };
+
+  const isArxiv = decodedUrl.includes('arxiv.org');
+  const remoteOk = (isArxiv && networkStatus['arxiv'] !== false);
+
+  // arXiv: iframe 直连（跨域，IDM 只能认了）
+  if (remoteOk) {
+    loaded = false;
+    $('#pdfStatus').textContent = '🌐 arXiv 加载中...';
+    $('#pdfStatus').style.display = '';
+    frame.onload = () => { loaded=true; $('#pdfStatus').style.display='none'; };
+    frame.src = decodedUrl;
+
+    pdfTimeout = setTimeout(async () => {
+      if (loaded) return;
+      if (!hkFallback) { $('#pdfStatus').textContent='⚠️ arXiv 超时'; return; }
+      // fallback to HK, use fetch→blob to beat IDM
+      $('#pdfStatus').textContent = '⏳ arXiv 超时，走 HK 服务器...';
+      try {
+        const resp = await fetch(hkFallback, { cache:'default' });
+        const blobUrl = URL.createObjectURL(await resp.blob());
+        $('#pdfStatus').textContent = '';
+        frame.src = blobUrl;
+      } catch(e) { $('#pdfStatus').textContent = '⚠️ HK 加载失败'; }
+    }, 5000);
+  } else {
+    // arXiv down / local / HF → use HK with fetch→blob
+    const src = hkFallback || decodedUrl;
+    $('#pdfStatus').textContent = hkFallback ? '📂 HK 服务器加载中...' : '⏳ 加载中...';
+    $('#pdfStatus').style.display = '';
+    try {
+      const resp = await fetch(src, { cache:'default' });
+      const blobUrl = URL.createObjectURL(await resp.blob());
+      $('#pdfStatus').textContent = '';
+      frame.src = blobUrl;
+    } catch(e) { $('#pdfStatus').textContent = '⚠️ 加载失败'; }
+  }
+
+  $('#pdfOverlay').classList.add('open');
+}
+
+function closePdf() {
+  if (pdfTimeout) { clearTimeout(pdfTimeout); pdfTimeout = null; }
+  $('#pdfOverlay').classList.remove('open');
+  $('#pdfFrame').src = '';
+  currentPdf = null;
+}
+
+// ═══════════════ SEARCH ═══════════════════════════════
+function searchPapers(q) {
+  q = (q||'').toLowerCase().trim();
+  if (q.length<2) { $$('.card').forEach(c=>c.style.outline=''); return; }
+  fetch(`${API}/papers?q=${encodeURIComponent(q)}&limit=10`).then(r=>r.json()).then(ps=>{
+    const matched = new Set(ps.map(p=>p.module_id));
+    $$('.card').forEach(c=>{
+      const m=[...c.classList].find(x=>x.startsWith('card-'))?.replace('card-','');
+      c.style.outline=matched.has(m)?'2px solid var(--green)':'';
+    });
+  });
+}
+
+// ═══════════════ EVENTS ═══════════════════════════════
+if (typeof document !== 'undefined') {
+  document.addEventListener('DOMContentLoaded', () => {
+    init();
+    $('.search-input').addEventListener('input', e => searchPapers(e.target.value));
+    $('#modalClose').addEventListener('click', closeModal);
+    $('#overlay').addEventListener('click', e => { if (e.target===$('#overlay')) closeModal(); });
+  });
+}
+
+</script>
 </body>
 </html>