* { box-sizing: border-box; }
    html, body { margin: 0; }
    body { font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif; background: #f4f7fb; color: #172033; line-height: 1.72; }
    .app { display: flex; min-height: 100vh; }
    .sidebar { width: 280px; padding: 22px 16px; background: #ffffff; border-right: 1px solid #d8e0ec; position: sticky; top: 0; height: 100vh; overflow: auto; }
    .sidebar h2 { margin: 0 0 14px; font-size: 18px; color: #0f766e; }
    .sidebar a { display: block; color: #334155; text-decoration: none; padding: 8px 10px; border-radius: 6px; margin-bottom: 4px; font-size: 14px; }
    .sidebar a:hover, .sidebar a.active { background: #e8f5f2; color: #0f766e; font-weight: 700; }
    .main { flex: 1; padding: 36px min(5vw, 56px); min-width: 0; }
    .article { max-width: 980px; margin: 0 auto; background: #fff; border: 1px solid #d8e0ec; border-radius: 8px; padding: 30px; box-shadow: 0 10px 28px rgba(15, 23, 42, .06); }
    .breadcrumb { color: #64748b; font-size: 14px; margin-bottom: 10px; }
    h1 { margin: 0 0 14px; font-size: 30px; color: #111827; letter-spacing: 0; }
    h2 { margin-top: 26px; color: #0f766e; font-size: 22px; }
    h3 { color: #1f2937; font-size: 18px; }
    p { margin: 12px 0; }
    .summary { background: #eef8f6; border-left: 4px solid #0f766e; padding: 14px 16px; border-radius: 6px; }
    .grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 12px; margin: 18px 0; }
    .card { border: 1px solid #d8e0ec; border-radius: 8px; padding: 14px; background: #fbfdff; }
    .card strong { color: #0f766e; }
    table { width: 100%; border-collapse: collapse; margin: 16px 0; }
    th, td { border: 1px solid #d8e0ec; padding: 10px; text-align: left; vertical-align: top; }
    th { background: #f1f5f9; color: #1f2937; }
    .diagram { margin: 20px 0; padding: 12px; border: 1px solid #d8e0ec; border-radius: 8px; background: #f8fafc; }
    .footer-nav { margin-top: 28px; }
    .footer-nav a { display: inline-block; padding: 10px 14px; border-radius: 6px; background: #0f766e; color: #fff; text-decoration: none; font-weight: 700; }
    footer { margin-top: 22px; color: #64748b; font-size: 13px; }
    @media (max-width: 820px) {
      .sidebar { position: static; height: auto; }
      .main { padding: 20px 12px; }
      .article { padding: 20px; }
      h1 { font-size: 26px; }
    }