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+<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>Excel → Markdown 转换器</title>
+  <style>
+    * { box-sizing: border-box; margin: 0; padding: 0; }
+
+    :root {
+      --bg: #0f0f0f;
+      --surface: #1a1a1a;
+      --surface2: #252525;
+      --border: #333;
+      --text: #e0e0e0;
+      --text-dim: #888;
+      --accent: #3b82f6;
+      --accent-hover: #60a5fa;
+      --success: #22c55e;
+    }
+
+    body {
+      font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
+      background: var(--bg);
+      color: var(--text);
+      height: 100vh;
+      display: flex;
+      flex-direction: column;
+    }
+
+    header {
+      padding: 14px 24px;
+      border-bottom: 1px solid var(--border);
+      display: flex;
+      align-items: center;
+      gap: 12px;
+      background: var(--surface);
+    }
+
+    header h1 {
+      font-size: 16px;
+      font-weight: 600;
+      color: var(--text);
+    }
+
+    header p {
+      font-size: 13px;
+      color: var(--text-dim);
+    }
+
+    .toolbar {
+      margin-left: auto;
+      display: flex;
+      gap: 8px;
+    }
+
+    .btn {
+      padding: 6px 14px;
+      border-radius: 6px;
+      border: none;
+      font-size: 13px;
+      font-weight: 500;
+      cursor: pointer;
+      transition: all 0.15s;
+    }
+
+    .btn-primary {
+      background: var(--accent);
+      color: #fff;
+    }
+
+    .btn-primary:hover { background: var(--accent-hover); }
+
+    .btn-ghost {
+      background: transparent;
+      color: var(--text-dim);
+      border: 1px solid var(--border);
+    }
+
+    .btn-ghost:hover { background: var(--surface2); color: var(--text); }
+
+    main {
+      flex: 1;
+      display: grid;
+      grid-template-columns: 1fr 1fr;
+      gap: 0;
+      overflow: hidden;
+    }
+
+    .panel {
+      display: flex;
+      flex-direction: column;
+      overflow: hidden;
+    }
+
+    .panel-left {
+      border-right: 1px solid var(--border);
+    }
+
+    .panel-header {
+      padding: 10px 16px;
+      background: var(--surface);
+      border-bottom: 1px solid var(--border);
+      font-size: 12px;
+      font-weight: 600;
+      text-transform: uppercase;
+      letter-spacing: 0.05em;
+      color: var(--text-dim);
+      display: flex;
+      align-items: center;
+      gap: 8px;
+    }
+
+    .panel-header .dot {
+      width: 6px; height: 6px;
+      border-radius: 50%;
+      background: var(--accent);
+    }
+
+    textarea {
+      flex: 1;
+      background: var(--surface);
+      color: var(--text);
+      border: none;
+      outline: none;
+      resize: none;
+      padding: 16px;
+      font-family: 'SF Mono', 'Cascadia Code', 'Fira Code', monospace;
+      font-size: 13px;
+      line-height: 1.6;
+    }
+
+    textarea::placeholder { color: var(--text-dim); }
+
+    .panel-right {
+      background: var(--surface);
+    }
+
+    .output-wrap {
+      flex: 1;
+      overflow-y: auto;
+      padding: 16px;
+    }
+
+    #output {
+      font-family: 'SF Mono', 'Cascadia Code', 'Fira Code', monospace;
+      font-size: 13px;
+      line-height: 1.7;
+      white-space: pre-wrap;
+      word-break: break-word;
+    }
+
+    .preview-toggle {
+      display: flex;
+      gap: 4px;
+    }
+
+    .preview-toggle button {
+      padding: 4px 10px;
+      border-radius: 4px;
+      border: 1px solid var(--border);
+      background: transparent;
+      color: var(--text-dim);
+      font-size: 12px;
+      cursor: pointer;
+    }
+
+    .preview-toggle button.active {
+      background: var(--accent);
+      color: #fff;
+      border-color: var(--accent);
+    }
+
+    .md-preview {
+      display: none;
+    }
+
+    .md-preview.active { display: block; }
+
+    table.md-table {
+      border-collapse: collapse;
+      width: 100%;
+      font-size: 13px;
+    }
+
+    table.md-table th,
+    table.md-table td {
+      border: 1px solid var(--border);
+      padding: 6px 12px;
+      text-align: left;
+    }
+
+    table.md-table th {
+      background: var(--surface2);
+      font-weight: 600;
+    }
+
+    table.md-table tr:nth-child(even) td {
+      background: var(--bg);
+    }
+
+    .status {
+      font-size: 11px;
+      color: var(--text-dim);
+      margin-left: auto;
+    }
+
+    .status.success { color: var(--success); }
+  </style>
+</head>
+<body>
+
+<header>
+  <div>
+    <h1>Excel → Markdown 转换器</h1>
+    <p>粘贴 Excel 表格内容，自动生成 Markdown 表格</p>
+  </div>
+  <div class="toolbar">
+    <div class="preview-toggle">
+      <button id="btn-markdown" class="active">Markdown</button>
+      <button id="btn-preview">预览</button>
+    </div>
+    <button class="btn btn-ghost" id="btn-copy">复制 Markdown</button>
+    <button class="btn btn-primary" id="btn-convert">转换</button>
+  </div>
+</header>
+
+<main>
+  <div class="panel panel-left">
+    <div class="panel-header">
+      <span class="dot"></span>
+      Excel / CSV 内容
+      <span class="status" id="status-left"></span>
+    </div>
+    <textarea
+      id="input"
+      placeholder="在这里粘贴 Excel 表格内容（支持从 Excel、Numbers、Google Sheets 直接粘贴）
+
+💡 粘贴后会自动转换，也可以点击「转换」按钮手动触发"
+    ></textarea>
+  </div>
+
+  <div class="panel panel-right">
+    <div class="panel-header">
+      <span class="dot" style="background: var(--success)"></span>
+      Markdown 输出
+      <span class="status" id="status-right"></span>
+    </div>
+    <div class="output-wrap">
+      <div id="output-raw" class="md-preview"></div>
+      <div id="output" class="md-preview active"></div>
+    </div>
+  </div>
+</main>
+
+<script>
+  const $ = id => document.getElementById(id);
+  const input = $('input');
+  const outputRaw = $('output-raw');
+  const output = $('output');
+  const statusLeft = $('status-left');
+  const statusRight = $('status-right');
+
+  let convertMode = 'markdown'; // 'markdown' or 'preview'
+
+  function excelToMarkdown(text) {
+    const lines = text.trim().split('\n');
+    if (lines.length === 0) return '';
+
+    const rows = lines.map(line => {
+      // Split by tab, handling quoted fields
+      const cells = [];
+      let current = '';
+      let inQuotes = false;
+
+      for (let i = 0; i < line.length; i++) {
+        const ch = line[i];
+        if (ch === '"') {
+          inQuotes = !inQuotes;
+        } else if (ch === '\t' && !inQuotes) {
+          cells.push(current.trim());
+          current = '';
+        } else {
+          current += ch;
+        }
+      }
+      cells.push(current.trim());
+      return cells;
+    });
+
+    if (rows.length === 0) return '';
+
+    // Detect delimiter: try tab first, fall back to comma or semicolon
+    const firstRow = rows[0];
+    const allTabs = rows.every(r => r.length === firstRow.length && firstRow.every(c => c.includes('\t') || c.trim() === ''));
+
+    // Normalize: handle if the split by tab didn't work well
+    // Fallback: split by comma if no tabs found
+    const normalizedRows = firstRow.length <= 1 && lines[0].includes(',')
+      ? lines.map(line => line.split(',').map(c => c.trim().replace(/^"|"$/g, '')))
+      : rows;
+
+    const colCount = normalizedRows[0].length;
+    const justified = normalizedRows.map(row => {
+      while (row.length < colCount) row.push('');
+      return row.slice(0, colCount);
+    });
+
+    // Build markdown
+    const header = justified[0];
+    const separator = header.map(() => '---');
+
+    const mdRows = [header, separator, ...justified.slice(1)];
+
+    // Find max width per column
+    const colWidths = [];
+    for (let c = 0; c < colCount; c++) {
+      let max = 0;
+      for (let r = 0; r < mdRows.length; r++) {
+        const cell = mdRows[r][c] || '';
+        const len = cell.replace(/\|/g, '\\|').length;
+        if (len > max) max = len;
+      }
+      colWidths.push(max);
+    }
+
+    // Build the table string
+    const separatorRow = '| ' + colWidths.map(w => '-'.repeat(w)).join(' | ') + ' |';
+
+    const lines_out = mdRows.map((row, ri) => {
+      const cells = row.map((cell, ci) => {
+        const cleaned = cell.replace(/\|/g, '\\|');
+        const padded = ri === 1 ? separatorRow : (cleaned + ' '.repeat(colWidths[ci] - cleaned.replace(/\|/g, '\\|').length));
+        return padded;
+      });
+      return '| ' + cells.join(' | ') + ' |';
+    });
+
+    return lines_out.join('\n');
+  }
+
+  function renderMarkdownTable(markdown) {
+    const lines = markdown.split('\n').filter(l => l.trim());
+    if (lines.length < 2) return markdown;
+
+    // Simple markdown table renderer
+    const rows = [];
+    let header = [];
+    let inBody = false;
+
+    for (const line of lines) {
+      if (line.startsWith('|') && line.endsWith('|')) {
+        const cells = line.split('|').slice(1, -1).map(c => c.trim());
+        if (cells.every(c => c.match(/^-+$/))) {
+          inBody = true;
+          continue;
+        }
+        if (!inBody) {
+          header = cells;
+        } else {
+          rows.push(cells);
+        }
+      }
+    }
+
+    if (header.length === 0) return markdown;
+
+    let html = '<table class="md-table"><thead><tr>';
+    header.forEach(h => html += `<th>${escapeHtml(h)}</th>`);
+    html += '</tr></thead><tbody>';
+    rows.forEach(row => {
+      html += '<tr>';
+      row.forEach(cell => html += `<td>${escapeHtml(cell)}</td>`);
+      html += '</tr>';
+    });
+    html += '</tbody></table>';
+    return html;
+  }
+
+  function escapeHtml(str) {
+    return str.replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;').replace(/"/g,'&quot;');
+  }
+
+  function convert() {
+    const text = input.value;
+    if (!text.trim()) {
+      output.textContent = '';
+      outputRaw.textContent = '';
+      statusRight.textContent = '';
+      return;
+    }
+
+    const markdown = excelToMarkdown(text);
+    outputRaw.textContent = markdown;
+    output.innerHTML = renderMarkdownTable(markdown);
+    statusRight.textContent = '已转换';
+    statusRight.className = 'status success';
+    setTimeout(() => { statusRight.textContent = ''; statusRight.className = 'status'; }, 2000);
+  }
+
+  // Auto-convert on paste
+  input.addEventListener('input', () => {
+    statusLeft.textContent = input.value.split('\n').length + ' 行';
+    convert();
+  });
+
+  // Manual convert
+  $('btn-convert').addEventListener('click', convert);
+
+  // Copy
+  $('btn-copy').addEventListener('click', () => {
+    const text = outputRaw.textContent || output.textContent;
+    if (!text) return;
+    navigator.clipboard.writeText(text).then(() => {
+      const btn = $('btn-copy');
+      const orig = btn.textContent;
+      btn.textContent = '已复制!';
+      setTimeout(() => btn.textContent = orig, 1500);
+    });
+  });
+
+  // Toggle preview
+  $('btn-markdown').addEventListener('click', () => {
+    convertMode = 'markdown';
+    $('btn-markdown').classList.add('active');
+    $('btn-preview').classList.remove('active');
+    outputRaw.classList.add('active');
+    output.classList.remove('active');
+  });
+
+  $('btn-preview').addEventListener('click', () => {
+    convertMode = 'preview';
+    $('btn-preview').classList.add('active');
+    $('btn-markdown').classList.remove('active');
+    output.classList.add('active');
+    outputRaw.classList.remove('active');
+  });
+</script>
+
+</body>
+</html>
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