diff --git a/.gitignore b/.gitignore
index 418e0c1..abb1d44 100644
--- a/.gitignore
+++ b/.gitignore
@@ -189,6 +189,10 @@ data_cache/
 *.gif
 *.svg
 
+# Exception: backtest viewer HTML files
+!visualization/backtest_viewer.html
+!framework_v2/backtest_viewer.html
+
 
 # Report files (keep examples)
 report*.csv
diff --git a/visualization/backtest_viewer.html b/visualization/backtest_viewer.html
new file mode 100644
index 0000000..c04f353
--- /dev/null
+++ b/visualization/backtest_viewer.html
@@ -0,0 +1,714 @@
+<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+<meta charset="UTF-8">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
+<title>ETF轮动策略回测回放器</title>
+<style>
+* { margin: 0; padding: 0; box-sizing: border-box; }
+body { font-family: -apple-system, 'SF Mono', 'Menlo', monospace; background: #0d1117; color: #c9d1d9; font-size: 13px; }
+
+.loader { display: flex; align-items: center; justify-content: center; height: 100vh; flex-direction: column; gap: 16px; }
+.loader input[type="file"] { display: none; }
+.loader label { padding: 16px 32px; background: #238636; color: #fff; border-radius: 8px; cursor: pointer; font-size: 16px; }
+.loader label:hover { background: #2ea043; }
+.loader .hint { color: #8b949e; }
+
+.app { display: none; height: 100vh; flex-direction: column; overflow: hidden; }
+.app.active { display: flex; }
+
+/* Header */
+.header { display: flex; align-items: center; gap: 12px; padding: 8px 16px; background: #161b22; border-bottom: 1px solid #30363d; flex-shrink: 0; }
+.header .date-display { font-size: 18px; font-weight: 600; color: #58a6ff; min-width: 120px; }
+.header .nav-val { font-size: 16px; font-weight: 600; min-width: 100px; }
+.header .daily-ret { font-size: 14px; min-width: 80px; font-weight: 600; }
+.header .rebal-badge { background: #da3633; color: #fff; padding: 2px 8px; border-radius: 4px; font-size: 11px; }
+
+/* Controls */
+.controls { display: flex; align-items: center; gap: 8px; padding: 6px 16px; background: #161b22; border-bottom: 1px solid #30363d; flex-shrink: 0; }
+.controls button { background: #21262d; border: 1px solid #30363d; color: #c9d1d9; padding: 4px 12px; border-radius: 4px; cursor: pointer; font-size: 12px; }
+.controls button:hover { background: #30363d; }
+.controls button:active { background: #484f58; }
+.controls input[type="date"] { background: #21262d; border: 1px solid #30363d; color: #c9d1d9; padding: 4px 8px; border-radius: 4px; font-size: 12px; }
+.controls input[type="range"] { width: 80px; }
+.controls .speed-label { color: #8b949e; font-size: 11px; }
+.controls .day-counter { color: #8b949e; font-size: 11px; margin-left: auto; }
+
+/* Nav Chart */
+.chart-container { height: 180px; padding: 8px 16px; background: #0d1117; flex-shrink: 0; border-bottom: 1px solid #30363d; position: relative; }
+.chart-container canvas { width: 100%; height: 100%; }
+
+/* Stats panel */
+.stats-panel { display: flex; gap: 16px; padding: 8px 16px; background: #161b22; border-bottom: 1px solid #30363d; flex-shrink: 0; flex-wrap: wrap; }
+.stat-item { display: flex; flex-direction: column; min-width: 90px; }
+.stat-item .stat-label { color: #8b949e; font-size: 10px; text-transform: uppercase; letter-spacing: 0.5px; }
+.stat-item .stat-value { font-size: 14px; font-weight: 600; margin-top: 1px; }
+
+/* Main content */
+.main { display: grid; grid-template-columns: 280px 1fr; flex: 1; overflow: hidden; }
+
+/* Holdings panel */
+.holdings-panel { padding: 12px; border-right: 1px solid #30363d; overflow-y: auto; background: #161b22; }
+.holdings-panel h3 { color: #8b949e; font-size: 11px; text-transform: uppercase; letter-spacing: 1px; margin-bottom: 8px; }
+.holding-card { background: #0d1117; border: 1px solid #30363d; border-radius: 6px; padding: 10px; margin-bottom: 8px; }
+.holding-card.positive { border-left: 3px solid #3fb950; }
+.holding-card.negative { border-left: 3px solid #da3633; }
+.holding-card .code { font-weight: 600; color: #58a6ff; font-size: 14px; }
+.holding-card .name { color: #8b949e; font-size: 11px; }
+.holding-card .details { display: grid; grid-template-columns: 1fr 1fr; gap: 4px; margin-top: 6px; font-size: 11px; }
+.holding-card .details .label { color: #8b949e; }
+.holding-card .details .value { text-align: right; }
+
+/* Ranking table */
+.ranking-panel { display: flex; flex-direction: column; overflow: hidden; }
+.ranking-table-wrap { flex: 1; overflow-y: auto; padding: 0 12px 12px; }
+.ranking-panel h3 { color: #8b949e; font-size: 11px; text-transform: uppercase; letter-spacing: 1px; padding: 12px 12px 8px; flex-shrink: 0; }
+table { width: 100%; border-collapse: collapse; font-size: 12px; }
+thead { position: sticky; top: 0; background: #0d1117; z-index: 1; }
+th { text-align: left; padding: 6px 8px; color: #8b949e; border-bottom: 1px solid #30363d; font-weight: 500; }
+td { padding: 5px 8px; border-bottom: 1px solid #21262d; }
+tr.held { background: rgba(56, 139, 253, 0.1); }
+tr.held td:first-child { border-left: 3px solid #58a6ff; }
+tr.below-threshold { color: #484f58; }
+.positive { color: #3fb950; }
+.negative { color: #da3633; }
+.neutral { color: #8b949e; }
+
+/* Rebalance bar */
+.rebalance-bar { padding: 8px 16px; background: #1c1206; border-top: 1px solid #5a3e00; flex-shrink: 0; display: none; font-size: 12px; }
+.rebalance-bar.active { display: flex; gap: 16px; align-items: center; flex-wrap: wrap; }
+.rebalance-bar .tag-in { background: #238636; color: #fff; padding: 1px 6px; border-radius: 3px; font-size: 11px; }
+.rebalance-bar .tag-out { background: #da3633; color: #fff; padding: 1px 6px; border-radius: 3px; font-size: 11px; }
+</style>
+</head>
+<body>
+
+<div class="loader" id="loader">
+  <div style="font-size: 20px; font-weight: 600;">ETF 轮动策略回测回放器</div>
+  <div class="hint">加载 backtest_detail.json 开始回放</div>
+  <label for="file-input">选择 JSON 文件</label>
+  <input type="file" id="file-input" accept=".json">
+  <div class="hint" id="load-status"></div>
+</div>
+
+<div class="app" id="app">
+  <div class="header">
+    <span class="date-display" id="date-display"></span>
+    <span class="nav-val" id="nav-display"></span>
+    <span class="daily-ret" id="ret-display"></span>
+    <span class="rebal-badge" id="rebal-badge" style="display:none">调仓</span>
+  </div>
+
+  <div class="controls">
+    <button id="btn-prev" title="上一天 (←)">&#9664; 前一天</button>
+    <button id="btn-next" title="下一天 (→)">后一天 &#9654;</button>
+    <button id="btn-prev-rebal" title="上一调仓日">&#9664;&#9664; 上一调仓</button>
+    <button id="btn-next-rebal" title="下一调仓日">下一调仓 &#9654;&#9654;</button>
+    <input type="date" id="date-picker">
+    <button id="btn-play" title="播放/暂停 (Space)">&#9654; 播放</button>
+    <span class="speed-label">速度:</span>
+    <input type="range" id="speed-slider" min="1" max="10" value="5">
+    <span class="day-counter" id="day-counter"></span>
+  </div>
+
+  <div class="chart-container">
+    <canvas id="nav-chart"></canvas>
+  </div>
+
+  <div class="stats-panel" id="stats-panel"></div>
+
+  <div class="main">
+    <div class="holdings-panel">
+      <h3>当日持仓</h3>
+      <div id="holdings-cards"></div>
+    </div>
+    <div class="ranking-panel">
+      <h3>全部标的排名 (按动量排序)</h3>
+      <div class="ranking-table-wrap">
+        <table>
+          <thead>
+            <tr>
+              <th>#</th>
+              <th>代码</th>
+              <th>名称</th>
+              <th>大类</th>
+              <th>动量</th>
+              <th>阈值</th>
+              <th>指数价</th>
+              <th>ETF价</th>
+              <th>指数收益</th>
+              <th>ETF收益</th>
+              <th>溢价率</th>
+              <th>持仓</th>
+            </tr>
+          </thead>
+          <tbody id="ranking-body"></tbody>
+        </table>
+      </div>
+    </div>
+  </div>
+
+  <div class="rebalance-bar" id="rebalance-bar"></div>
+</div>
+
+<script>
+let DATA = null;
+let currentIdx = 0;
+let playing = false;
+let playTimer = null;
+let rebalanceDays = [];
+
+const $ = id => document.getElementById(id);
+
+// File loading
+$('file-input').addEventListener('change', e => {
+  const file = e.target.files[0];
+  if (!file) return;
+  $('load-status').textContent = '加载中...';
+  const reader = new FileReader();
+  reader.onload = ev => {
+    try {
+      DATA = JSON.parse(ev.target.result);
+      initApp();
+    } catch (err) {
+      $('load-status').textContent = '解析失败: ' + err.message;
+    }
+  };
+  reader.readAsText(file);
+});
+
+function initApp() {
+  $('loader').style.display = 'none';
+  $('app').classList.add('active');
+
+  // Build rebalance day index
+  rebalanceDays = [];
+  DATA.days.forEach((d, i) => { if (d.is_rebalance) rebalanceDays.push(i); });
+
+  // Set date picker range
+  $('date-picker').min = DATA.days[0].date;
+  $('date-picker').max = DATA.days[DATA.days.length - 1].date;
+
+  drawChart();
+  render(0);
+}
+
+// Navigation
+$('btn-prev').addEventListener('click', () => navigate(-1));
+$('btn-next').addEventListener('click', () => navigate(1));
+$('btn-prev-rebal').addEventListener('click', () => navigateRebalance(-1));
+$('btn-next-rebal').addEventListener('click', () => navigateRebalance(1));
+$('date-picker').addEventListener('change', e => {
+  const target = e.target.value;
+  const idx = DATA.days.findIndex(d => d.date === target);
+  if (idx >= 0) { currentIdx = idx; render(currentIdx); drawChartMarker(); }
+});
+
+$('btn-play').addEventListener('click', togglePlay);
+
+document.addEventListener('keydown', e => {
+  if (e.target.tagName === 'INPUT') return;
+  if (e.key === 'ArrowLeft') { e.preventDefault(); navigate(-1); }
+  if (e.key === 'ArrowRight') { e.preventDefault(); navigate(1); }
+  if (e.key === ' ') { e.preventDefault(); togglePlay(); }
+});
+
+function navigate(delta) {
+  const next = currentIdx + delta;
+  if (next >= 0 && next < DATA.days.length) {
+    currentIdx = next;
+    render(currentIdx);
+    drawChartMarker();
+  }
+}
+
+function navigateRebalance(dir) {
+  if (dir > 0) {
+    const next = rebalanceDays.find(i => i > currentIdx);
+    if (next !== undefined) { currentIdx = next; render(currentIdx); drawChartMarker(); }
+  } else {
+    const prev = [...rebalanceDays].reverse().find(i => i < currentIdx);
+    if (prev !== undefined) { currentIdx = prev; render(currentIdx); drawChartMarker(); }
+  }
+}
+
+function togglePlay() {
+  playing = !playing;
+  $('btn-play').innerHTML = playing ? '&#9646;&#9646; 暂停' : '&#9654; 播放';
+  if (playing) {
+    playTick();
+  } else {
+    clearTimeout(playTimer);
+  }
+}
+
+function playTick() {
+  if (!playing) return;
+  if (currentIdx < DATA.days.length - 1) {
+    currentIdx++;
+    render(currentIdx);
+    drawChartMarker();
+    const speed = parseInt($('speed-slider').value);
+    const delay = 1100 - speed * 100; // 1000ms ~ 100ms
+    playTimer = setTimeout(playTick, delay);
+  } else {
+    playing = false;
+    $('btn-play').innerHTML = '&#9654; 播放';
+  }
+}
+
+function fmtPct(v, decimals) {
+  if (v === null || v === undefined) return '-';
+  return (v * 100).toFixed(decimals !== undefined ? decimals : 2) + '%';
+}
+
+function fmtNum(v, decimals) {
+  if (v === null || v === undefined) return '-';
+  return Number(v).toFixed(decimals !== undefined ? decimals : 2);
+}
+
+function retClass(v) {
+  if (v === null || v === undefined) return 'neutral';
+  return v > 0 ? 'positive' : v < 0 ? 'negative' : 'neutral';
+}
+
+function render(idx) {
+  const day = DATA.days[idx];
+  const meta = DATA.meta;
+
+  // Header
+  $('date-display').textContent = day.date;
+  $('nav-display').textContent = '净值 ' + fmtNum(day.nav, 4);
+  $('nav-display').className = 'nav-val';
+
+  const retEl = $('ret-display');
+  retEl.textContent = (day.daily_return >= 0 ? '+' : '') + fmtPct(day.daily_return);
+  retEl.className = 'daily-ret ' + retClass(day.daily_return);
+
+  const badge = $('rebal-badge');
+  badge.style.display = day.is_rebalance ? 'inline' : 'none';
+
+  $('day-counter').textContent = `第 ${idx + 1} / ${DATA.days.length} 天  |  调仓 ${rebalanceDays.filter(i => i <= idx).length} 次`;
+  $('date-picker').value = day.date;
+
+  // Stats panel
+  renderStats(idx);
+
+  // Holdings cards
+  renderHoldings(day, meta);
+
+  // Ranking table
+  renderRanking(day, meta);
+
+  // Rebalance bar
+  renderRebalanceBar(day, meta);
+}
+
+function renderStats(idx) {
+  const panel = $('stats-panel');
+  const days = DATA.days;
+
+  // Slice up to current day
+  const navs = [];
+  for (let i = 0; i <= idx; i++) {
+    if (days[i].nav !== null) navs.push(days[i].nav);
+  }
+  if (navs.length < 2) {
+    panel.innerHTML = '<span class="stat-item"><span class="stat-label">等待数据...</span></span>';
+    return;
+  }
+
+  const startNav = navs[0];
+  const curNav = navs[navs.length - 1];
+  const totalReturn = curNav / startNav - 1;
+  const tradingDays = navs.length;
+  const years = tradingDays / 252;  // 统一使用 252 天（A股标准），与 rotation.py 一致
+  const cagr = years > 0 ? Math.pow(curNav / startNav, 1 / years) - 1 : 0;
+
+  // Max drawdown
+  let maxDD = 0;
+  let peak = navs[0];
+  for (let i = 1; i < navs.length; i++) {
+    if (navs[i] > peak) peak = navs[i];
+    const dd = navs[i] / peak - 1;
+    if (dd < maxDD) maxDD = dd;
+  }
+
+  // Volatility & Sharpe（使用 252 天，与 rotation.py 一致）
+  const rets = [];
+  for (let i = 1; i < navs.length; i++) {
+    rets.push(navs[i] / navs[i-1] - 1);
+  }
+  const meanRet = rets.reduce((a, b) => a + b, 0) / rets.length;
+  const variance = rets.reduce((a, b) => a + (b - meanRet) ** 2, 0) / rets.length;
+  const vol = Math.sqrt(variance) * Math.sqrt(252);
+  const sharpe = vol > 0 ? (meanRet * 252) / vol : 0;
+  const calmar = maxDD !== 0 ? cagr / Math.abs(maxDD) : 0;
+
+  // Rebalance count & avg holding days
+  const rebalCount = rebalanceDays.filter(i => i <= idx).length;
+  let avgHoldDays = '-';
+  if (rebalCount > 1) {
+    let totalHold = 0;
+    let prevRebal = rebalanceDays[0];
+    let cnt = 0;
+    for (const ri of rebalanceDays) {
+      if (ri > idx) break;
+      if (cnt > 0) totalHold += ri - prevRebal;
+      prevRebal = ri;
+      cnt++;
+    }
+    if (cnt > 1) avgHoldDays = (totalHold / (cnt - 1)).toFixed(1);
+  }
+
+  // Win rate (daily)
+  const winDays = rets.filter(r => r > 0).length;
+  const winRate = rets.length > 0 ? winDays / rets.length : 0;
+
+  // Year-to-date return
+  const curYear = days[idx].date.substring(0, 4);
+  let ytdReturn = null;
+  for (let i = idx; i >= 0; i--) {
+    if (days[i].date.substring(0, 4) !== curYear) {
+      const prevYearEndNav = days[i].nav;
+      if (prevYearEndNav && curNav) ytdReturn = curNav / prevYearEndNav - 1;
+      break;
+    }
+  }
+
+  const items = [
+    { label: 'CAGR', value: fmtPct(cagr), cls: retClass(cagr) },
+    { label: '累计收益', value: fmtPct(totalReturn), cls: retClass(totalReturn) },
+    { label: '最大回撤', value: fmtPct(maxDD), cls: 'negative' },
+    { label: '年化波动', value: fmtPct(vol), cls: 'neutral' },
+    { label: '夏普', value: fmtNum(sharpe, 3), cls: retClass(sharpe) },
+    { label: 'Calmar', value: fmtNum(calmar, 3), cls: retClass(calmar) },
+    { label: '胜率', value: fmtPct(winRate), cls: 'neutral' },
+    { label: '调仓次数', value: String(rebalCount), cls: 'neutral' },
+    { label: '平均持仓', value: avgHoldDays + '天', cls: 'neutral' },
+    { label: '本年收益', value: ytdReturn !== null ? fmtPct(ytdReturn) : '-', cls: retClass(ytdReturn) },
+    { label: '交易天数', value: String(tradingDays), cls: 'neutral' },
+  ];
+
+  panel.innerHTML = items.map(it =>
+    `<div class="stat-item"><span class="stat-label">${it.label}</span><span class="stat-value ${it.cls}">${it.value}</span></div>`
+  ).join('');
+}
+
+function renderHoldings(day, meta) {
+  const container = $('holdings-cards');
+  if (!day.holdings || day.holdings.length === 0) {
+    container.innerHTML = '<div style="color:#8b949e;padding:16px;text-align:center;">无持仓</div>';
+    return;
+  }
+
+  let html = '';
+  for (const code of day.holdings) {
+    const a = day.assets[code];
+    if (!a) continue;
+    const info = meta.codes[code] || {};
+    const cumEtf = a.cum_return_etf;
+    const cumIdx = a.cum_return_idx;
+    const mainCum = cumEtf !== null && cumEtf !== undefined ? cumEtf : cumIdx;
+    const cls = mainCum !== null && mainCum !== undefined ? (mainCum >= 0 ? 'positive' : 'negative') : '';
+
+    html += `<div class="holding-card ${cls}">
+      <span class="code">${code}</span> <span class="name">${info.name || ''}</span>
+      ${info.etf ? `<span class="name"> (${info.etf})</span>` : ''}
+      <div class="details">
+        <span class="label">入场日</span><span class="value">${a.entry_date || '-'}</span>
+        <span class="label">持有天数</span><span class="value">${a.holding_days || 0}</span>
+        <span class="label">ETF累计</span><span class="value ${retClass(cumEtf)}">${fmtPct(cumEtf)}</span>
+        <span class="label">指数累计</span><span class="value ${retClass(cumIdx)}">${fmtPct(cumIdx)}</span>
+        <span class="label">今日ETF</span><span class="value ${retClass(a.etf_return_ctc)}">${fmtPct(a.etf_return_ctc)}</span>
+        <span class="label">今日指数</span><span class="value ${retClass(a.index_return)}">${fmtPct(a.index_return)}</span>
+        <span class="label">动量</span><span class="value">${fmtNum(a.momentum, 4)}</span>
+        <span class="label">大类</span><span class="value">${info.market || '-'}</span>
+      </div>
+    </div>`;
+  }
+  container.innerHTML = html;
+}
+
+function renderRanking(day, meta) {
+  const tbody = $('ranking-body');
+  const assets = day.assets;
+  const codes = Object.keys(assets);
+
+  // Sort by momentum descending, nulls last
+  codes.sort((a, b) => {
+    const ma = assets[a].momentum;
+    const mb = assets[b].momentum;
+    if (ma === null && mb === null) return 0;
+    if (ma === null) return 1;
+    if (mb === null) return -1;
+    return mb - ma;
+  });
+
+  const threshold = codes.length > 0 && assets[codes[0]].threshold !== null
+    ? assets[codes[0]].threshold : 0;
+
+  let html = '';
+  let thresholdDrawn = false;
+
+  for (let i = 0; i < codes.length; i++) {
+    const code = codes[i];
+    const a = assets[code];
+    const info = meta.codes[code] || {};
+    const isHeld = a.is_held;
+    const belowThreshold = a.momentum !== null && a.momentum < threshold;
+
+    // Insert threshold separator row before first below-threshold item
+    if (!thresholdDrawn && belowThreshold) {
+      html += `<tr><td colspan="12" style="color:#da3633;font-size:11px;text-align:center;border-bottom:2px dashed #da3633;padding:2px;">--- 动态阈值: ${fmtNum(threshold, 4)} ---</td></tr>`;
+      thresholdDrawn = true;
+    }
+
+    let rowClass = '';
+    if (isHeld) rowClass += ' held';
+    if (belowThreshold) rowClass += ' below-threshold';
+
+    // Use rank from data, but show sequential for display
+    const displayRank = a.rank !== null ? a.rank : '-';
+
+    html += `<tr class="${rowClass}">
+      <td>${displayRank}</td>
+      <td>${code}</td>
+      <td>${info.name || ''}</td>
+      <td>${info.market || ''}</td>
+      <td>${fmtNum(a.momentum, 4)}</td>
+      <td>${fmtNum(threshold, 4)}</td>
+      <td>${fmtNum(a.index_close, 2)}</td>
+      <td>${a.etf_close !== null ? fmtNum(a.etf_close, 3) : '-'}</td>
+      <td class="${retClass(a.index_return)}">${fmtPct(a.index_return)}</td>
+      <td class="${retClass(a.etf_return_ctc)}">${fmtPct(a.etf_return_ctc)}</td>
+      <td class="${a.premium > 0.05 ? 'negative' : a.premium < -0.02 ? 'positive' : 'neutral'}">${a.premium !== null && a.premium !== undefined ? fmtPct(a.premium) : '-'}</td>
+      <td>${isHeld ? '<span style="color:#58a6ff">&#9679;</span>' : ''}</td>
+    </tr>`;
+  }
+
+  // If threshold line not drawn yet (all above), add it at the bottom
+  if (!thresholdDrawn && threshold > 0) {
+    html += `<tr class="threshold-line"><td colspan="12" style="color:#da3633;font-size:11px;text-align:center;">--- 动态阈值: ${fmtNum(threshold, 4)} ---</td></tr>`;
+  }
+
+  tbody.innerHTML = html;
+}
+
+function renderRebalanceBar(day, meta) {
+  const bar = $('rebalance-bar');
+  if (!day.is_rebalance) {
+    bar.classList.remove('active');
+    return;
+  }
+  bar.classList.add('active');
+
+  let html = '<strong>调仓:</strong>';
+
+  if (day.added.length > 0) {
+    html += ' 调入: ';
+    html += day.added.map(c => {
+      const name = (meta.codes[c] || {}).name || '';
+      return `<span class="tag-in">${c} (${name})</span>`;
+    }).join(' ');
+  }
+
+  if (day.removed.length > 0) {
+    html += ' 调出: ';
+    html += day.removed.map(c => {
+      const name = (meta.codes[c] || {}).name || '';
+      return `<span class="tag-out">${c} (${name})</span>`;
+    }).join(' ');
+  }
+
+  // Calculate turnover
+  const prevHoldings = currentIdx > 0 ? DATA.days[currentIdx - 1].holdings : [];
+  const swapped = day.removed.length;
+  const total = Math.max(prevHoldings.length, 1);
+  const turnover = swapped / total;
+  const cost = turnover * meta.trade_cost;
+  html += `<span style="color:#8b949e;margin-left:12px;">换手 ${fmtPct(turnover, 0)} | 成本 ${fmtPct(cost, 2)}</span>`;
+
+  bar.innerHTML = html;
+}
+
+// ==================== Chart ====================
+let chartCanvas, chartCtx;
+let chartData = { navs: [], dates: [], rebalIdx: [] };
+
+function drawChart() {
+  chartCanvas = $('nav-chart');
+  chartCtx = chartCanvas.getContext('2d');
+
+  // Retina support
+  const rect = chartCanvas.parentElement.getBoundingClientRect();
+  const dpr = window.devicePixelRatio || 1;
+  chartCanvas.width = rect.width * dpr;
+  chartCanvas.height = rect.height * dpr;
+  chartCtx.scale(dpr, dpr);
+  chartCanvas.style.width = rect.width + 'px';
+  chartCanvas.style.height = rect.height + 'px';
+
+  chartData.navs = DATA.days.map(d => d.nav);
+  chartData.dates = DATA.days.map(d => d.date);
+  chartData.rebalIdx = rebalanceDays;
+
+  drawChartFull();
+  drawChartMarker();
+}
+
+function drawChartFull() {
+  const ctx = chartCtx;
+  const W = chartCanvas.width / (window.devicePixelRatio || 1);
+  const H = chartCanvas.height / (window.devicePixelRatio || 1);
+  const pad = { top: 20, right: 60, bottom: 20, left: 10 };
+  const cw = W - pad.left - pad.right;
+  const ch = H - pad.top - pad.bottom;
+
+  const navs = chartData.navs;
+  const minNav = Math.min(...navs.filter(v => v !== null)) * 0.98;
+  const maxNav = Math.max(...navs.filter(v => v !== null)) * 1.02;
+  const n = navs.length;
+
+  ctx.clearRect(0, 0, W, H);
+
+  // Grid lines
+  ctx.strokeStyle = '#21262d';
+  ctx.lineWidth = 0.5;
+  for (let i = 0; i <= 4; i++) {
+    const y = pad.top + ch * i / 4;
+    ctx.beginPath();
+    ctx.moveTo(pad.left, y);
+    ctx.lineTo(W - pad.right, y);
+    ctx.stroke();
+    const val = maxNav - (maxNav - minNav) * i / 4;
+    ctx.fillStyle = '#484f58';
+    ctx.font = '10px monospace';
+    ctx.textAlign = 'left';
+    ctx.fillText(val.toFixed(2), W - pad.right + 4, y + 3);
+  }
+
+  // Nav line
+  ctx.strokeStyle = '#58a6ff';
+  ctx.lineWidth = 1.5;
+  ctx.beginPath();
+  for (let i = 0; i < n; i++) {
+    const x = pad.left + (i / (n - 1)) * cw;
+    const y = pad.top + (1 - (navs[i] - minNav) / (maxNav - minNav)) * ch;
+    if (i === 0) ctx.moveTo(x, y);
+    else ctx.lineTo(x, y);
+  }
+  ctx.stroke();
+
+  // Rebalance dots
+  ctx.fillStyle = 'rgba(218, 54, 51, 0.6)';
+  for (const ri of chartData.rebalIdx) {
+    const x = pad.left + (ri / (n - 1)) * cw;
+    const y = pad.top + (1 - (navs[ri] - minNav) / (maxNav - minNav)) * ch;
+    ctx.beginPath();
+    ctx.arc(x, y, 2, 0, Math.PI * 2);
+    ctx.fill();
+  }
+
+  // Store layout for marker
+  chartData.layout = { pad, cw, ch, minNav, maxNav, n, W, H };
+}
+
+function drawChartMarker() {
+  if (!chartData.layout) return;
+  const { pad, cw, ch, minNav, maxNav, n, W, H } = chartData.layout;
+
+  // Redraw full chart then add marker
+  drawChartFull();
+
+  const ctx = chartCtx;
+  const x = pad.left + (currentIdx / (n - 1)) * cw;
+
+  // Vertical line
+  ctx.strokeStyle = 'rgba(255,255,255,0.5)';
+  ctx.lineWidth = 1;
+  ctx.setLineDash([3, 3]);
+  ctx.beginPath();
+  ctx.moveTo(x, pad.top);
+  ctx.lineTo(x, pad.top + ch);
+  ctx.stroke();
+  ctx.setLineDash([]);
+
+  // Dot
+  const nav = chartData.navs[currentIdx];
+  const y = pad.top + (1 - (nav - minNav) / (maxNav - minNav)) * ch;
+  ctx.fillStyle = '#fff';
+  ctx.beginPath();
+  ctx.arc(x, y, 4, 0, Math.PI * 2);
+  ctx.fill();
+
+  // Label
+  ctx.fillStyle = '#fff';
+  ctx.font = '11px monospace';
+  ctx.textAlign = x > W / 2 ? 'right' : 'left';
+  const labelX = x > W / 2 ? x - 8 : x + 8;
+  ctx.fillText(fmtNum(nav, 4), labelX, y - 8);
+}
+
+// ==================== Chart interaction (click & drag) ====================
+let isDragging = false;
+
+function xToIndex(clientX) {
+  if (!chartData.layout) return -1;
+  const rect = chartCanvas.getBoundingClientRect();
+  const { pad, cw, n } = chartData.layout;
+  const x = clientX - rect.left - pad.left;
+  const ratio = Math.max(0, Math.min(1, x / cw));
+  return Math.round(ratio * (n - 1));
+}
+
+function chartNavigateTo(clientX) {
+  const idx = xToIndex(clientX);
+  if (idx >= 0 && idx < DATA.days.length && idx !== currentIdx) {
+    currentIdx = idx;
+    render(currentIdx);
+    drawChartMarker();
+  }
+}
+
+$('nav-chart').addEventListener('mousedown', e => {
+  if (!DATA) return;
+  isDragging = true;
+  chartNavigateTo(e.clientX);
+});
+
+window.addEventListener('mousemove', e => {
+  if (!isDragging) return;
+  chartNavigateTo(e.clientX);
+});
+
+window.addEventListener('mouseup', () => {
+  isDragging = false;
+});
+
+// Touch support
+$('nav-chart').addEventListener('touchstart', e => {
+  if (!DATA) return;
+  isDragging = true;
+  chartNavigateTo(e.touches[0].clientX);
+}, { passive: true });
+
+window.addEventListener('touchmove', e => {
+  if (!isDragging) return;
+  chartNavigateTo(e.touches[0].clientX);
+}, { passive: true });
+
+window.addEventListener('touchend', () => {
+  isDragging = false;
+});
+
+// Cursor style
+$('nav-chart').style.cursor = 'crosshair';
+
+// Resize handler
+window.addEventListener('resize', () => {
+  if (DATA) { drawChart(); }
+});
+</script>
+</body>
+</html>
