diff --git a/site/index.html b/site/index.html
index b3820a3..73a83e9 100644
--- a/site/index.html
+++ b/site/index.html
@@ -4,15 +4,24 @@
 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1">
 <title>Awesome Coding Agents — Rankings &amp; History</title>
+<meta name="description" content="Daily-refreshed ranking of open-source AI coding agents by GitHub stars, with 7-day deltas and star-history charts.">
+<meta property="og:title" content="Awesome Coding Agents — Rankings &amp; History">
+<meta property="og:description" content="Daily-refreshed ranking of open-source AI coding agents by GitHub stars, with 7-day deltas and star-history charts.">
+<meta property="og:url" content="https://tiennm99.github.io/awesome-coding-agents/">
+<meta property="og:type" content="website">
+<meta name="theme-color" content="#ffffff" media="(prefers-color-scheme: light)">
+<meta name="theme-color" content="#0d1117" media="(prefers-color-scheme: dark)">
+<link rel="icon" href="data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20100%20100%22%3E%3Ctext%20y%3D%22.9em%22%20font-size%3D%2290%22%3E%E2%AD%90%3C%2Ftext%3E%3C%2Fsvg%3E">
 <style>
   :root {
-    --bg: #ffffff; --fg: #1f2328; --muted: #656d76; --border: #d0d7de;
+    --bg: #ffffff; --fg: #1f2328; --muted: #59626b; --border: #d0d7de;
     --accent: #0969da; --chip: #f6f8fa; --chip-on: #0969da; --chip-on-fg: #fff;
     --pos: #1a7f37; --neg: #cf222e; --row-hover: #f6f8fa;
+    color-scheme: light dark;
   }
   @media (prefers-color-scheme: dark) {
     :root {
-      --bg: #0d1117; --fg: #e6edf3; --muted: #8b949e; --border: #30363d;
+      --bg: #0d1117; --fg: #e6edf3; --muted: #9ba3ad; --border: #30363d;
       --accent: #58a6ff; --chip: #21262d; --chip-on: #1f6feb; --chip-on-fg: #fff;
       --pos: #3fb950; --neg: #f85149; --row-hover: #161b22;
     }
@@ -26,16 +35,33 @@
   h1 { font-size: 1.6rem; margin: 0 0 .25rem; }
   .sub { color: var(--muted); margin-bottom: 1.25rem; }
   .sub a { color: var(--accent); }
-  .chips { display: flex; flex-wrap: wrap; gap: .5rem; margin: 1rem 0; }
-  .chips button {
+  .vh {
+    position: absolute; width: 1px; height: 1px; margin: -1px; padding: 0;
+    overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
+  }
+  .toolbar { display: flex; flex-wrap: wrap; gap: .5rem .75rem; align-items: center; margin: 1rem 0 .5rem; }
+  #q {
+    border: 1px solid var(--border); background: var(--bg); color: var(--fg);
+    border-radius: 6px; padding: .4rem .75rem; font: inherit; min-width: 14rem; flex: 1 1 14rem; max-width: 24rem;
+  }
+  #q::placeholder { color: var(--muted); opacity: 1; }
+  .chips { display: flex; flex-wrap: wrap; gap: .5rem; margin: .5rem 0 1rem; }
+  .chips button, .btn {
     border: 1px solid var(--border); background: var(--chip); color: var(--fg);
-    border-radius: 999px; padding: .25rem .85rem; cursor: pointer; font-size: .9rem;
+    border-radius: 999px; padding: .3rem .85rem; cursor: pointer; font-size: .9rem;
+    transition: background-color .15s ease, border-color .15s ease;
+  }
+  .btn { border-radius: 6px; }
+  .chips button.on, .btn[aria-pressed="true"] { background: var(--chip-on); color: var(--chip-on-fg); border-color: var(--chip-on); }
+  .chips button:hover, .btn:hover { border-color: var(--accent); }
+  a:focus-visible, button:focus-visible, input:focus-visible, th[data-k]:focus-visible {
+    outline: 2px solid var(--accent); outline-offset: 2px;
   }
-  .chips button.on { background: var(--chip-on); color: var(--chip-on-fg); border-color: var(--chip-on); }
   .tablewrap { overflow-x: auto; border: 1px solid var(--border); border-radius: 8px; }
   table { border-collapse: collapse; width: 100%; min-width: 780px; }
   th, td { padding: .5rem .75rem; text-align: left; border-top: 1px solid var(--border); }
-  thead th { border-top: none; background: var(--chip); cursor: pointer; user-select: none; white-space: nowrap; }
+  thead th { border-top: none; background: var(--chip); user-select: none; white-space: nowrap; }
+  thead th[data-k] { cursor: pointer; }
   thead th .dir { color: var(--accent); }
   tbody tr:hover { background: var(--row-hover); }
   td.num, th.num { text-align: right; font-variant-numeric: tabular-nums; }
@@ -47,10 +73,28 @@
     display: inline-block; font-size: .75rem; padding: .05rem .5rem;
     border: 1px solid var(--border); border-radius: 999px; color: var(--muted);
   }
-  h2 { font-size: 1.2rem; margin: 2rem 0 .5rem; }
+  tr.stale td { color: var(--muted); }
+  .stalebadge {
+    display: inline-block; font-size: .72rem; padding: 0 .45rem; margin-left: .4rem;
+    border: 1px solid var(--border); border-radius: 999px; color: var(--muted);
+    text-transform: uppercase; letter-spacing: .03em; vertical-align: middle;
+  }
+  td.empty { text-align: center; color: var(--muted); padding: 1.5rem; }
+  h2 { font-size: 1.2rem; margin: 0; }
+  .charthead { display: flex; align-items: center; justify-content: space-between; gap: .75rem; margin: 2rem 0 .5rem; flex-wrap: wrap; }
   .chartwrap { position: relative; height: 460px; border: 1px solid var(--border); border-radius: 8px; padding: 1rem; }
+  .chartmsg { color: var(--muted); text-align: center; padding-top: 4rem; }
   .hint { color: var(--muted); font-size: .85rem; margin: .35rem 0 0; }
   #err { color: var(--neg); }
+  noscript p { border: 1px solid var(--border); border-radius: 8px; padding: 1rem; }
+  noscript a { color: var(--accent); }
+  @media (pointer: coarse) {
+    .chips button, .btn, #q { min-height: 44px; }
+    thead th { padding-block: .85rem; }
+  }
+  @media (prefers-reduced-motion: reduce) {
+    *, *::before, *::after { transition: none !important; animation: none !important; }
+  }
 </style>
 </head>
 <body>
@@ -60,26 +104,41 @@
     <span id="meta">loading…</span> ·
     <a href="https://github.com/tiennm99/awesome-coding-agents">GitHub repo</a>
   </div>
-  <div id="err"></div>
+  <div id="err" role="alert"></div>
+
+  <noscript>
+    <p>This dashboard needs JavaScript to render the ranking table and charts.
+    You can view the same ranking in the
+    <a href="https://github.com/tiennm99/awesome-coding-agents#readme">project README on GitHub</a>.</p>
+  </noscript>
+
+  <div class="toolbar">
+    <label class="vh" for="q">Search repositories by name or description</label>
+    <input id="q" type="search" placeholder="Search repos…" autocomplete="off">
+  </div>
+  <div class="chips" id="chips" role="group" aria-label="Filter by category"></div>
 
-  <div class="chips" id="chips"></div>
   <div class="tablewrap"><table id="tbl">
     <thead><tr>
-      <th data-k="rank" class="num">#</th>
-      <th data-k="nameWithOwner">Repo</th>
-      <th data-k="stars" class="num">Stars</th>
-      <th data-k="delta7d" class="num">Δ7d</th>
-      <th data-k="category">Category</th>
-      <th data-k="language">Language</th>
-      <th data-k="pushedAt">Last push</th>
-      <th>Description</th>
+      <th scope="col" data-k="rank" class="num" tabindex="0">#</th>
+      <th scope="col" data-k="nameWithOwner" tabindex="0">Repo</th>
+      <th scope="col" data-k="stars" class="num" tabindex="0">Stars</th>
+      <th scope="col" data-k="delta7d" class="num" tabindex="0">Δ7d</th>
+      <th scope="col" data-k="category" tabindex="0">Category</th>
+      <th scope="col" data-k="language" tabindex="0">Language</th>
+      <th scope="col" data-k="pushedAt" tabindex="0">Last push</th>
+      <th scope="col">Description</th>
     </tr></thead>
     <tbody></tbody>
   </table></div>
 
-  <h2>Star history</h2>
-  <div class="chartwrap"><canvas id="chart"></canvas></div>
-  <p class="hint">Top 12 repos shown by default — click legend entries to toggle series. The category filter above also filters the chart.</p>
+  <div class="charthead">
+    <h2>Star history</h2>
+    <button type="button" id="scaleToggle" class="btn" aria-pressed="false">Log scale</button>
+  </div>
+  <div class="chartwrap"><canvas id="chart" role="img"
+    aria-label="Line chart of GitHub star history over time for the repositories listed in the table above."></canvas></div>
+  <p class="hint">Top 12 repos shown by default — click legend entries to toggle series. The category filter and search above also filter the chart.</p>
 
 <script src="https://cdn.jsdelivr.net/npm/chart.js@4.4.9/dist/chart.umd.min.js"></script>
 <script>
@@ -98,80 +157,148 @@
   document.getElementById('meta').textContent =
     'Last updated ' + data.updatedAt + ' · ' + rows.length + ' repos tracked';
 
+  const staleCutoff = new Date();
+  staleCutoff.setMonth(staleCutoff.getMonth() - 6);
+  const isStale = r => r.pushedAt && new Date(r.pushedAt) < staleCutoff;
+
   // --- category filter chips ---
   const cats = ['all', ...new Set(rows.map(r => r.category).filter(Boolean).sort())];
   let activeCat = 'all';
   const chipBox = document.getElementById('chips');
   for (const c of cats) {
     const b = document.createElement('button');
+    b.type = 'button';
     b.textContent = c;
     b.className = c === activeCat ? 'on' : '';
+    b.setAttribute('aria-pressed', String(c === activeCat));
     b.onclick = () => {
       activeCat = c;
-      chipBox.querySelectorAll('button').forEach(x => x.classList.toggle('on', x === b));
+      chipBox.querySelectorAll('button').forEach(x => {
+        const on = x === b;
+        x.classList.toggle('on', on);
+        x.setAttribute('aria-pressed', String(on));
+      });
       renderTable(); renderChart();
     };
     chipBox.appendChild(b);
   }
 
-  const visible = () => activeCat === 'all' ? rows : rows.filter(r => r.category === activeCat);
+  // --- text search (filters table + chart) ---
+  let query = '';
+  const qInput = document.getElementById('q');
+  let qTimer;
+  qInput.addEventListener('input', () => {
+    clearTimeout(qTimer);
+    qTimer = setTimeout(() => {
+      query = qInput.value.trim().toLowerCase();
+      renderTable(); renderChart();
+    }, 150);
+  });
+
+  const visible = () => rows.filter(r =>
+    (activeCat === 'all' || r.category === activeCat) &&
+    (!query ||
+      r.nameWithOwner.toLowerCase().includes(query) ||
+      String(r.description || '').toLowerCase().includes(query)));
 
   // --- sortable table ---
   const fmtStars = n => n >= 1e6 ? (n / 1e6).toFixed(1) + 'M' : n >= 1e3 ? (n / 1e3).toFixed(1) + 'k' : String(n);
   let sortKey = 'rank', sortAsc = true;
   document.querySelectorAll('thead th[data-k]').forEach(th => {
-    th.onclick = () => {
+    const activate = () => {
       const k = th.dataset.k;
       if (sortKey === k) sortAsc = !sortAsc;
       else { sortKey = k; sortAsc = (k === 'rank' || k === 'nameWithOwner' || k === 'category' || k === 'language'); }
       renderTable();
     };
+    th.onclick = activate;
+    th.addEventListener('keydown', e => {
+      if (e.key === 'Enter' || e.key === ' ') { e.preventDefault(); activate(); }
+    });
   });
 
   function renderTable() {
     const list = [...visible()].sort((a, b) => {
+      if (sortKey === 'delta7d') {
+        // repos without a 7-day baseline always sort last, either direction
+        if (a.hasDelta !== b.hasDelta) return a.hasDelta ? -1 : 1;
+        if (!a.hasDelta) return 0;
+        return sortAsc ? a.delta7d - b.delta7d : b.delta7d - a.delta7d;
+      }
       const va = a[sortKey], vb = b[sortKey];
       const cmp = typeof va === 'number' ? va - vb : String(va).localeCompare(String(vb));
       return sortAsc ? cmp : -cmp;
     });
-    document.querySelectorAll('thead th .dir').forEach(s => s.remove());
-    const th = document.querySelector('thead th[data-k="' + sortKey + '"]');
-    if (th) th.insertAdjacentHTML('beforeend', ' <span class="dir">' + (sortAsc ? '▲' : '▼') + '</span>');
+    document.querySelectorAll('thead th[data-k]').forEach(th => {
+      th.querySelector('.dir')?.remove();
+      if (th.dataset.k === sortKey) {
+        th.setAttribute('aria-sort', sortAsc ? 'ascending' : 'descending');
+        th.insertAdjacentHTML('beforeend', ' <span class="dir" aria-hidden="true">' + (sortAsc ? '▲' : '▼') + '</span>');
+      } else {
+        th.removeAttribute('aria-sort');
+      }
+    });
 
     const esc = s => String(s ?? '').replace(/[&<>"]/g, c => ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;' }[c]));
-    document.querySelector('#tbl tbody').innerHTML = list.map(r => `
-      <tr>
+    const tbody = document.querySelector('#tbl tbody');
+    if (!list.length) {
+      tbody.innerHTML = '<tr><td class="empty" colspan="8">No repos match your filters.</td></tr>';
+      return;
+    }
+    tbody.innerHTML = list.map(r => `
+      <tr${isStale(r) ? ' class="stale"' : ''}>
         <td class="num">${r.rank}</td>
         <td><a class="repo" href="${esc(r.url)}">${esc(r.nameWithOwner)}</a></td>
         <td class="num">${fmtStars(r.stars)}</td>
-        <td class="num ${r.delta7d > 0 ? 'pos' : r.delta7d < 0 ? 'neg' : ''}">${r.hasDelta ? (r.delta7d > 0 ? '+' : '') + r.delta7d : '—'}</td>
+        <td class="num ${r.hasDelta && r.delta7d > 0 ? 'pos' : r.hasDelta && r.delta7d < 0 ? 'neg' : ''}">${r.hasDelta ? (r.delta7d > 0 ? '+' : '') + r.delta7d : '—'}</td>
         <td><span class="cat">${esc(r.category || '—')}</span></td>
         <td>${esc(r.language || '')}</td>
-        <td>${esc(r.pushedAt)}</td>
+        <td>${esc(r.pushedAt)}${isStale(r) ? ' <span class="stalebadge">stale</span>' : ''}</td>
         <td class="desc">${esc(r.description)}${r.notes ? ' · <em>' + esc(r.notes) + '</em>' : ''}</td>
       </tr>`).join('');
   }
 
+  renderTable();
+
   // --- star-history line chart ---
+  const chartWrap = document.querySelector('.chartwrap');
+  if (!window.Chart) {
+    chartWrap.innerHTML = '<p class="chartmsg">Chart could not be loaded (the Chart.js CDN is unreachable or blocked). The ranking table above still works.</p>';
+    document.getElementById('scaleToggle').disabled = true;
+    return;
+  }
+
   const dates = data.history.map(s => s.date);
-  const color = i => 'hsl(' + Math.round(i * 137.508) % 360 + ' 65% 50%)';
+  const isDark = matchMedia('(prefers-color-scheme: dark)').matches;
+  // darker lines on light bg / lighter on dark bg to keep >=3:1 against background
+  const color = i => 'hsl(' + Math.round(i * 137.508) % 360 + ' 70% ' + (isDark ? 62 : 38) + '%)';
   const styles = getComputedStyle(document.documentElement);
   Chart.defaults.color = styles.getPropertyValue('--muted').trim();
   Chart.defaults.borderColor = styles.getPropertyValue('--border').trim();
   let chart;
+  let yType = 'linear';
+  const hiddenState = {}; // repo key -> hidden bool, survives chart re-renders
 
   function renderChart() {
+    // Degraded mode: filter/search handlers still call this after the early
+    // CDN-failure return; without the guard they hit TDZ consts and throw.
+    if (!window.Chart) return;
     const list = visible();
-    const datasets = list.map((r, i) => ({
-      label: r.nameWithOwner,
-      data: data.history.map(s => s.stars[r.key] ?? null),
-      borderColor: color(i),
-      backgroundColor: color(i),
-      pointRadius: 0,
-      borderWidth: 2,
-      spanGaps: true,
-      hidden: i >= 12, // top 12 visible; rest toggleable via legend
-    }));
+    const datasets = list.map((r, i) => {
+      const pts = data.history.map(s => s.stars[r.key] ?? null);
+      const nPoints = pts.filter(v => v != null).length;
+      return {
+        label: r.nameWithOwner,
+        repoKey: r.key,
+        data: pts,
+        borderColor: color(i),
+        backgroundColor: color(i),
+        pointRadius: nPoints < 2 ? 3 : 0, // single snapshots need a visible dot
+        borderWidth: 2,
+        spanGaps: true,
+        hidden: r.key in hiddenState ? hiddenState[r.key] : i >= 12, // top 12 visible by default
+      };
+    });
     if (chart) chart.destroy();
     chart = new Chart(document.getElementById('chart'), {
       type: 'line',
@@ -180,18 +307,34 @@
         responsive: true, maintainAspectRatio: false, animation: false,
         interaction: { mode: 'nearest', intersect: false },
         scales: {
-          y: { ticks: { callback: v => fmtStars(v) } },
+          y: { type: yType, ticks: { callback: v => fmtStars(v) } },
           x: { ticks: { maxTicksLimit: 12 } },
         },
         plugins: {
-          legend: { position: 'bottom', labels: { boxWidth: 12, boxHeight: 12 } },
+          legend: {
+            position: 'bottom',
+            labels: { boxWidth: 12, boxHeight: 12 },
+            onClick(e, item, legend) {
+              Chart.defaults.plugins.legend.onClick.call(this, e, item, legend);
+              const ds = legend.chart.data.datasets[item.datasetIndex];
+              hiddenState[ds.repoKey] = !legend.chart.isDatasetVisible(item.datasetIndex);
+            },
+          },
           tooltip: { callbacks: { label: c => c.dataset.label + ': ' + (c.parsed.y ?? '—').toLocaleString() } },
         },
       },
     });
+    document.getElementById('chart').setAttribute('aria-label',
+      'Line chart of GitHub star history over time for ' + list.length + ' repositories. The same data is in the table above.');
   }
 
-  renderTable();
+  const scaleBtn = document.getElementById('scaleToggle');
+  scaleBtn.onclick = () => {
+    yType = yType === 'linear' ? 'logarithmic' : 'linear';
+    scaleBtn.setAttribute('aria-pressed', String(yType === 'logarithmic'));
+    if (chart) { chart.options.scales.y.type = yType; chart.update(); }
+  };
+
   renderChart();
 })();
 </script>