:root {
      --primary: #2563eb;
      --accent: #06b6d4;
      --bg: #f8fafc;
      --text: #0f172a;
      --card-radius: 1rem;
      --pill-radius: 2rem;
      --soft-shadow: 0 10px 25px -8px rgba(37, 99, 235, 0.12);
    }

    body {
      background-color: var(--bg);
      color: var(--text);
      font-family: 'Inter', '思源黑体', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      font-size: 0.95rem;
      line-height: 1.6;
    }

    h1, h2, h3, h4, .font-song {
      font-family: '思源宋体', 'Source Han Serif SC', 'Noto Serif SC', serif;
      font-weight: 600;
      letter-spacing: 0.02em;
    }

    /* 滚动进度条 (顶部) */
    #scrollProgress {
      position: fixed;
      top: 0; left: 0;
      height: 4px;
      width: 0%;
      background: linear-gradient(90deg, var(--primary), var(--accent));
      z-index: 9999;
      border-radius: 0 4px 4px 0;
      transition: width 0.1s linear;
    }

    /* 吸顶导航 */
    .sticky-nav {
      position: sticky;
      top: 0;
      z-index: 1030;
      background: rgba(248, 250, 252, 0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(37, 99, 235, 0.1);
      padding: 0.5rem 0;
    }

    .navbar-brand {
      font-weight: 800;
      font-size: 1.4rem;
      color: var(--primary) !important;
      letter-spacing: -0.3px;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }
    .navbar-brand i {
      color: var(--accent);
      font-size: 1.6rem;
    }

    .nav-link-custom {
      font-weight: 500;
      color: var(--text) !important;
      margin: 0 0.25rem;
      padding: 0.4rem 0.8rem !important;
      border-radius: var(--pill-radius);
      transition: background 0.2s, color 0.2s;
    }
    .nav-link-custom:hover {
      background: rgba(37, 99, 235, 0.08);
      color: var(--primary) !important;
    }

    /* 胶囊通用 */
    .pill-btn {
      border-radius: var(--pill-radius);
      padding: 0.6rem 1.8rem;
      font-weight: 600;
      background: var(--primary);
      color: #fff;
      border: none;
      position: relative;
      overflow: hidden;
      z-index: 1;
      transition: box-shadow 0.2s;
    }
    .pill-btn::before {
      content: '';
      position: absolute;
      top: 0; left: -120%;
      width: 80%; height: 100%;
      background: linear-gradient(110deg, transparent, rgba(255,255,255,0.45), transparent);
      transform: skewX(-20deg);
      transition: left 0.5s;
      z-index: -1;
    }
    .pill-btn:hover::before {
      left: 140%;
    }
    .pill-btn:hover {
      box-shadow: 0 8px 18px rgba(37,99,235,0.25);
    }

    /* 卡片网格 */
    .feature-card {
      background: #fff;
      border-radius: var(--card-radius);
      padding: 1.2rem 1rem;
      box-shadow: var(--soft-shadow);
      height: 100%;
      border: 1px solid #eef2f7;
      transition: transform 0.2s, box-shadow 0.2s;
      opacity: 0;
      transform: translateY(30px);
      transition: opacity 0.6s cubic-bezier(.22,.61,.36,1), transform 0.6s cubic-bezier(.22,.61,.36,1), box-shadow 0.2s;
    }
    .feature-card.visible {
      opacity: 1;
      transform: translateY(0);
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: 0 18px 28px -10px rgba(6,182,212,0.18);
    }
    .feature-card i {
      color: var(--accent);
      font-size: 1.7rem;
      margin-bottom: 0.5rem;
    }

    /* 步骤条 */
    .step-wrapper {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 1rem;
    }
    .step-item {
      background: white;
      padding: 1.2rem 1.5rem;
      border-radius: var(--card-radius);
      box-shadow: var(--soft-shadow);
      flex: 1 1 180px;
      max-width: 210px;
      text-align: center;
      border-top: 3px solid var(--primary);
    }
    .step-num {
      background: var(--primary);
      color: white;
      width: 38px;
      height: 38px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border-radius: 50%;
      font-weight: 700;
      margin-bottom: 0.5rem;
      font-size: 1.1rem;
    }

    /* 双色块左右分屏 hero */
    .split-hero {
      background: linear-gradient(115deg, #ffffff 0%, #f0f7ff 100%);
      border-radius: 2rem;
      padding: 3rem 2.5rem;
      box-shadow: 0 15px 30px -15px rgba(37,99,235,0.15);
      display: flex;
      flex-wrap: wrap;
      align-items: center;
    }
    .split-left {
      flex: 1 1 300px;
      padding-right: 2rem;
    }
    .split-right {
      flex: 1 1 240px;
      text-align: center;
    }
    .typewriter h1 {
      display: inline-block;
      overflow: hidden;
      white-space: nowrap;
      border-right: 3px solid var(--accent);
      animation: blinkCursor 0.9s step-end infinite;
      font-size: 2.4rem;
      font-weight: 800;
      letter-spacing: 1px;
    }
    @keyframes blinkCursor { 50% { border-color: transparent; } }

    /* 区块通用 */
    .section {
      padding: 2.5rem 0 1.5rem;
    }
    .section-title {
      margin-bottom: 1.5rem;
      font-weight: 700;
      position: relative;
      display: inline-block;
      padding-bottom: 0.3rem;
    }
    .section-title::after {
      content: '';
      position: absolute;
      left: 0; bottom: -2px;
      width: 40px;
      height: 3px;
      background: var(--primary);
      border-radius: 4px;
    }

    /* 锚点偏移吸顶 */
    .anchor-offset {
      scroll-margin-top: 80px;
    }

    /* 友链区域 */
    .friend-links {
      background: #fff;
      border-radius: 2rem;
      padding: 1.5rem 1.8rem;
      margin: 2rem 0;
      box-shadow: var(--soft-shadow);
      border: 1px solid #e9eef5;
    }

    footer {
      background: #0f172a;
      color: #cbd5e1;
      border-radius: 2rem 2rem 0 0;
      padding: 2rem 0;
      margin-top: 2rem;
    }
    footer a {
      color: #bae6fd;
      text-decoration: none;
      font-weight: 500;
    }

    /* 小字高密度 */
    .dense-text {
      font-size: 0.9rem;
      line-height: 1.65;
    }

    /* 错落渐显 */
    .reveal-card {
      transition-delay: calc(var(--i) * 80ms);
    }

    @media (max-width: 768px) {
      .split-hero { padding: 2rem 1.2rem; }
      .typewriter h1 { font-size: 1.8rem; white-space: normal; border-right: none; }
    }

/* --- 子页面追加 --- */
/* 本页专属补充样式:关于页的章节卡片、时间线等 */
        .about-hero { padding: 4rem 0 2rem; }
.about-hero h1 { font-weight: 900; font-size: 2.4rem; color: var(--text); }
.about-hero .lead { color: #64748b; max-width: 760px; }
.about-section { padding: 3rem 0; border-bottom: 1px solid rgba(37,99,235,0.08); }
.about-section:last-child { border-bottom: none; }
.about-section h2 { font-weight: 800; font-size: 1.7rem; margin-bottom: 1.2rem; color: var(--text); }
.about-section h2 i { color: var(--primary); margin-right: 0.5rem; }
.about-section p { line-height: 1.9; color: #334155; }
.about-section ul { padding-left: 1.2rem; }
.about-section ul li { margin-bottom: 0.6rem; line-height: 1.8; color: #334155; }
.milestone-list { list-style: none; padding-left: 0; position: relative; }
.milestone-list::before { content: ''; position: absolute; left: 8px; top: 10px; bottom: 10px; width: 2px; background: linear-gradient(to bottom, var(--primary), var(--accent)); opacity: 0.3; }
.milestone-list li { position: relative; padding-left: 2.2rem; margin-bottom: 1.4rem; }
.milestone-list li::before { content: ''; position: absolute; left: 0; top: 8px; width: 18px; height: 18px; border-radius: 50%; background: var(--primary); border: 3px solid var(--bg); box-shadow: 0 0 0 2px var(--primary); }
.milestone-list li:nth-child(2)::before { background: var(--accent); box-shadow: 0 0 0 2px var(--accent); }
.milestone-list li:nth-child(3)::before { background: #8b5cf6; box-shadow: 0 0 0 2px #8b5cf6; }
.value-card { background: var(--bg); border-radius: var(--card-radius); padding: 1.8rem; height: 100%; box-shadow: var(--soft-shadow); border: 1px solid rgba(37,99,235,0.06); transition: transform 0.2s ease; }
.value-card:hover { transform: translateY(-4px); }
.value-card i { font-size: 2rem; color: var(--primary); margin-bottom: 0.8rem; display: inline-block; }
.value-card h4 { font-weight: 700; font-size: 1.2rem; margin-bottom: 0.6rem; color: var(--text); }
.value-card p { font-size: 0.95rem; color: #475569; line-height: 1.7; }
.stats-row { background: linear-gradient(135deg, rgba(37,99,235,0.06), rgba(6,182,212,0.06)); border-radius: var(--card-radius); padding: 2rem; margin-top: 2rem; }
.stats-row .stat-item { text-align: center; padding: 1rem; }
.stats-row .stat-num { font-size: 2.2rem; font-weight: 900; color: var(--primary); }
.stats-row .stat-label { font-size: 0.9rem; color: #64748b; margin-top: 0.3rem; }
.about-hero h1 { font-size: 1.9rem; }
.about-section h2 { font-size: 1.4rem; }
.value-card { padding: 1.3rem; }

/* --- 子页面追加 --- */
/* 免责声明页面专属样式(自动合并进站点CSS) */
        .legal-section {
            background: #ffffff;
            border-radius: var(--card-radius);
            padding: 2.5rem;
            margin-bottom: 1.5rem;
            box-shadow: var(--soft-shadow);
            border: 1px solid rgba(37, 99, 235, 0.08);
        }
.legal-section h2 {
            color: var(--primary);
            font-weight: 700;
            font-size: 1.5rem;
            margin-bottom: 1.25rem;
            padding-bottom: 0.75rem;
            border-bottom: 2px solid rgba(37, 99, 235, 0.15);
        }
.legal-section h3 {
            color: var(--text);
            font-weight: 600;
            font-size: 1.1rem;
            margin-top: 1.5rem;
            margin-bottom: 0.75rem;
        }
.legal-section p, .legal-section li {
            color: rgba(15, 23, 42, 0.8);
            line-height: 1.8;
            font-size: 0.95rem;
        }
.legal-section ul {
            padding-left: 1.25rem;
        }
.legal-section li {
            margin-bottom: 0.5rem;
        }
.legal-highlight {
            background: rgba(37, 99, 235, 0.05);
            border-left: 4px solid var(--primary);
            padding: 1rem 1.25rem;
            border-radius: 0.5rem;
            margin: 1.25rem 0;
        }
.legal-date {
            color: rgba(15, 23, 42, 0.5);
            font-size: 0.85rem;
            margin-bottom: 1.5rem;
        }
.legal-section {
                padding: 1.5rem;
            }
.legal-section h2 {
                font-size: 1.25rem;
            }