:root {
    --main: #38bdf8;
    --accent: #a78bfa;
    --bg: #0f172a;
    --text: #e2e8f0;
    --card-bg: #1e293b;
    --border-color: rgba(56, 189, 248, 0.25);
    --grid-line: rgba(56, 189, 248, 0.07);
    --muted: #94a3b8;
  }

  * {
    box-sizing: border-box;
  }

  body {
    background-color: var(--bg);
    color: var(--text);
    font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    font-size: 15px;
    line-height: 1.5;
    background-image: 
      linear-gradient(var(--grid-line) 1px, transparent 1px),
      linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
    background-size: 30px 30px;
    font-weight: 400;
    letter-spacing: 0.01em;
  }

  a {
    color: var(--main);
    text-decoration: none;
  }
  a:hover {
    color: var(--accent);
  }

  /* 紧凑高密度 */
  .container-custom {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
  }

  /* 导航 */
  .navbar-ym {
    background: rgba(15, 23, 42, 0.9);
    backdrop-filter: blur(6px);
    border-bottom: 1px solid var(--border-color);
    padding: 0.5rem 0;
    margin-bottom: 2rem;
  }
  .navbar-ym .navbar-brand {
    font-weight: 800;
    font-size: 1.6rem;
    color: var(--text);
    letter-spacing: -0.02em;
    display: inline-flex;
    align-items: center;
    gap: 8px;
  }
  .navbar-ym .navbar-brand i {
    color: var(--accent);
    font-size: 1.8rem;
  }
  .nav-link-custom {
    color: var(--muted) !important;
    font-weight: 500;
    margin: 0 0.4rem;
    padding: 0.5rem 0.6rem !important;
    border-bottom: 2px solid transparent;
    transition: 0.2s;
    font-size: 0.95rem;
  }
  .nav-link-custom:hover {
    color: var(--main) !important;
    border-bottom-color: var(--main);
  }
  .navbar-toggler {
    border-color: var(--border-color);
  }

  /* Hero 大数字 */
  .hero-stats {
    display: flex;
    flex-wrap: wrap;
    gap: 2.5rem;
    margin: 2rem 0 1.2rem;
  }
  .hero-stat-item {
    border-left: 2px solid var(--main);
    padding-left: 1.2rem;
  }
  .hero-stat-item .num {
    font-size: 2.8rem;
    font-weight: 800;
    line-height: 1.1;
    color: var(--text);
  }
  .hero-stat-item .label {
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--muted);
  }

  /* 时间线 / 步骤条 */
  .timeline-h {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 20px;
    margin: 2.5rem 0;
    position: relative;
    background: transparent;
  }
  .timeline-h::before {
    content: '';
    position: absolute;
    top: 20px;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--main), var(--accent));
    opacity: 0.25;
    z-index: 0;
  }
  .step-item {
    background: var(--bg);
    z-index: 1;
    padding-right: 12px;
    text-align: left;
    flex: 1 1 160px;
  }
  .step-marker {
    width: 42px;
    height: 42px;
    border: 2px solid var(--main);
    background: var(--bg);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    color: var(--main);
    font-size: 1.2rem;
    margin-bottom: 10px;
    box-shadow: 0 0 0 5px var(--bg);
  }
  .step-title {
    font-weight: 700;
    font-size: 1rem;
    color: var(--text);
  }
  .step-desc {
    font-size: 0.85rem;
    color: var(--muted);
    line-height: 1.4;
  }

  /* 卡片区 */
  .feature-icon-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 1rem;
    margin: 2rem 0;
  }
  .feature-card {
    background: transparent;
    border: 1px solid var(--border-color);
    padding: 1.2rem 1rem;
    transition: all 0.2s ease;
    border-radius: 0px;
    box-shadow: none;
  }
  .feature-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.6);
    border-color: var(--accent);
    background: var(--card-bg);
  }
  .feature-card i {
    font-size: 2rem;
    color: var(--accent);
    margin-bottom: 0.6rem;
  }
  .feature-card .card-title {
    font-weight: 700;
    font-size: 1.1rem;
  }
  .feature-card .card-text {
    font-size: 0.85rem;
    color: var(--muted);
  }

  /* FAQ折叠 */
  .accordion-ym .accordion-item {
    background: transparent;
    border: none;
    border-bottom: 1px solid var(--border-color);
    border-radius: 0;
  }
  .accordion-ym .accordion-button {
    background: transparent;
    color: var(--text);
    font-weight: 600;
    padding: 1rem 0.5rem;
    box-shadow: none;
    border-radius: 0;
    font-size: 1.05rem;
    border-bottom: 1px solid transparent;
  }
  .accordion-ym .accordion-button:not(.collapsed) {
    color: var(--main);
    background: transparent;
    box-shadow: none;
  }
  .accordion-ym .accordion-button:focus {
    box-shadow: none;
    border: none;
  }
  .accordion-ym .accordion-body {
    padding: 0.25rem 0.5rem 1rem;
    color: var(--muted);
    font-size: 0.9rem;
  }

  /* 介绍区块 步骤条横向时间线再次使用 */
  .intro-timeline {
    margin: 2rem 0;
  }
  .intro-timeline .step-item {
    flex-basis: 200px;
  }

  /* CTA */
  .cta-section {
    border: 1px solid var(--border-color);
    padding: 2.5rem 2rem;
    text-align: center;
    background: rgba(56, 189, 248, 0.02);
    margin: 3rem 0;
  }
  .cta-section h3 {
    font-weight: 800;
    font-size: 1.8rem;
  }
  .btn-ym {
    background: transparent;
    border: 2px solid var(--main);
    color: var(--main);
    padding: 0.6rem 2.2rem;
    font-weight: 600;
    border-radius: 0px;
    transition: 0.2s;
    font-size: 1rem;
    display: inline-block;
    margin-top: 1rem;
  }
  .btn-ym:hover {
    background: var(--main);
    color: var(--bg);
    box-shadow: none;
    transform: translateY(-2px);
  }

  /* 页脚 */
  .footer-ym {
    border-top: 1px solid var(--border-color);
    padding: 2.5rem 0 1rem;
    margin-top: 3rem;
    background: rgba(0,0,0,0.2);
  }
  .footer-links a {
    margin-right: 1.5rem;
    color: var(--muted);
    font-size: 0.9rem;
  }
  .footer-links a:hover {
    color: var(--main);
  }

  .friend-links {
    border-top: 1px dashed var(--border-color);
    margin-top: 2rem;
    padding-top: 1.2rem;
    font-size: 0.85rem;
  }

  /* 回到顶部 */
  #backToTop {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: var(--main);
    color: #0f172a;
    border: none;
    width: 44px;
    height: 44px;
    font-size: 1.2rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: 0.3s;
    z-index: 999;
    cursor: pointer;
    box-shadow: none;
  }
  #backToTop.show {
    opacity: 1;
    visibility: visible;
  }

  /* 图片懒加载渐显 */
  img[data-lazy] {
    background: #1e293b;
    opacity: 0.5;
    transition: opacity 0.5s;
  }
  img.lazy-loaded {
    opacity: 1;
  }

  h2.section-title {
    font-weight: 800;
    font-size: 1.9rem;
    border-left: 4px solid var(--accent);
    padding-left: 1rem;
    margin: 2.5rem 0 1rem;
    letter-spacing: -0.01em;
  }
  .text-accent { color: var(--accent); }
  .text-main { color: var(--main); }
  .text-muted-ym { color: var(--muted); }

/* --- 子页面追加 --- */
.ranking-page { padding: 60px 0; }
.ranking-header { text-align: center; margin-bottom: 50px; }
.ranking-header h1 { font-size: 2.5rem; font-weight: 800; margin-bottom: 15px; }
.ranking-header p { color: var(--muted); max-width: 600px; margin: 0 auto; }
.rank-tabs { display: flex; justify-content: center; gap: 10px; margin-bottom: 40px; flex-wrap: wrap; }
.rank-tab { padding: 10px 24px; border-radius: 30px; background: var(--card-bg); border: 1px solid var(--border-color); color: var(--text); cursor: pointer; font-weight: 500; transition: all 0.3s; }
.rank-tab:hover, .rank-tab.active { background: var(--main); color: #0f172a; border-color: var(--main); }
.rank-card { background: var(--card-bg); border: 1px solid var(--border-color); border-radius: 16px; padding: 24px; margin-bottom: 20px; transition: transform 0.3s, box-shadow 0.3s; }
.rank-card:hover { transform: translateY(-4px); box-shadow: 0 8px 30px rgba(56, 189, 248, 0.15); }
.rank-item { display: flex; align-items: center; gap: 20px; padding: 16px; border-radius: 12px; background: rgba(15, 23, 42, 0.5); margin-bottom: 12px; }
.rank-number { font-size: 1.5rem; font-weight: 900; color: var(--main); min-width: 50px; text-align: center; }
.rank-item:nth-child(1) .rank-number { color: #fbbf24; }
.rank-item:nth-child(2) .rank-number { color: #c0c0c0; }
.rank-item:nth-child(3) .rank-number { color: #cd7f32; }
.rank-info { flex: 1; }
.rank-title { font-weight: 600; font-size: 1.1rem; margin-bottom: 4px; }
.rank-meta { color: var(--muted); font-size: 0.9rem; }
.rank-stats { display: flex; gap: 20px; color: var(--muted); font-size: 0.85rem; }
.rank-stats i { color: var(--accent); margin-right: 5px; }
.rank-badge { background: linear-gradient(135deg, var(--main), var(--accent)); color: #fff; padding: 4px 12px; border-radius: 20px; font-size: 0.8rem; font-weight: 600; }
.rank-update { text-align: center; color: var(--muted); font-size: 0.9rem; margin-bottom: 30px; }
.rank-update i { color: var(--main); margin-right: 5px; }
.rank-feature { background: linear-gradient(135deg, rgba(56, 189, 248, 0.1), rgba(167, 139, 250, 0.1)); border: 1px solid var(--border-color); border-radius: 16px; padding: 30px; margin-top: 50px; }
.rank-feature h3 { color: var(--main); font-size: 1.3rem; margin-bottom: 20px; }
.rank-feature-list { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 20px; }
.rank-feature-item { background: var(--card-bg); padding: 20px; border-radius: 12px; border: 1px solid var(--border-color); }
.rank-feature-item i { color: var(--accent); font-size: 1.5rem; margin-bottom: 10px; }
.rank-feature-item h4 { font-size: 1rem; font-weight: 600; margin-bottom: 8px; }
.rank-feature-item p { color: var(--muted); font-size: 0.9rem; margin: 0; }
.rank-item { flex-direction: column; text-align: center; }
.rank-number { min-width: auto; }
.rank-stats { justify-content: center; flex-wrap: wrap; }
.rank-header h1 { font-size: 2rem; }

/* --- 子页面追加 --- */
/* 确保页面与首页视觉完全一致，同时不覆盖全局变量 */
        .about-hero {
            padding: 4.5rem 0 2.5rem;
            border-bottom: 1px solid var(--border-color);
        }
.section-title-ym {
            font-size: 1.75rem;
            font-weight: 700;
            letter-spacing: -0.02em;
            margin-bottom: 1.2rem;
        }
.section-title-ym .text-accent {
            color: var(--accent);
        }
.divider-ym {
            width: 70px;
            height: 4px;
            background: linear-gradient(90deg, var(--main), var(--accent));
            border-radius: 4px;
            margin: 0.5rem 0 2rem;
        }
.feature-icon-list i {
            color: var(--main);
        }
.intro-timeline .timeline-item {
            border-left: 2px solid var(--border-color);
            padding-left: 1.5rem;
            padding-bottom: 2rem;
            position: relative;
        }
.intro-timeline .timeline-item::before {
            content: "";
            position: absolute;
            left: -7px;
            top: 0;
            width: 12px;
            height: 12px;
            background: var(--main);
            border-radius: 50%;
            box-shadow: 0 0 12px rgba(56, 189, 248, 0.6);
        }
.timeline-year {
            font-weight: 700;
            color: var(--accent);
            font-size: 1.1rem;
        }
.quote-block {
            background: rgba(30, 41, 59, 0.6);
            border-left: 4px solid var(--accent);
            padding: 1.2rem 1.5rem;
            border-radius: 0 16px 16px 0;
        }
/* 覆盖 bootstrap 可能的白底类（确保没有卡片白底） */
        .card, .card-body, .card-title, .card-text {
            background: transparent;
            color: var(--text);
            border: none;
        }
.list-group-item {
            background: transparent;
            color: var(--text);
            border-color: var(--border-color);
        }

/* --- 子页面追加 --- */
.disclaimer-section { padding: 80px 0 40px; }
.disclaimer-hero { padding: 60px 0 40px; }
.disclaimer-hero h1 { font-size: 2.8rem; font-weight: 900; margin-bottom: 16px; }
.disclaimer-hero p { color: var(--muted); font-size: 1.1rem; max-width: 720px; }
.disclaimer-block { background: var(--card-bg); border: 1px solid var(--border-color); border-radius: 16px; padding: 32px 36px; margin-bottom: 28px; transition: transform 0.3s ease, box-shadow 0.3s ease; }
.disclaimer-block:hover { transform: translateY(-3px); box-shadow: 0 12px 32px rgba(56, 189, 248, 0.12); }
.disclaimer-block h2 { font-size: 1.6rem; font-weight: 800; color: var(--text); margin-bottom: 18px; display: flex; align-items: center; gap: 12px; }
.disclaimer-block h2 i { color: var(--main); font-size: 1.4rem; }
.disclaimer-block p, .disclaimer-block li { color: var(--muted); line-height: 1.8; font-size: 0.98rem; }
.disclaimer-block ul { padding-left: 20px; }
.disclaimer-block strong { color: var(--text); font-weight: 600; }
.last-updated { color: var(--muted); font-size: 0.9rem; margin-top: 40px; padding-top: 20px; border-top: 1px solid var(--border-color); }
.disclaimer-hero h1 { font-size: 2.1rem; }
.disclaimer-block { padding: 24px 20px; }
.disclaimer-block h2 { font-size: 1.3rem; }

/* --- 子页面追加 --- */
.privacy-section {
      background: var(--card-bg);
      border: 1px solid var(--border-color);
      border-radius: 18px;
      padding: 2rem 2rem 1.5rem;
      margin-bottom: 2.2rem;
      transition: box-shadow 0.3s ease;
    }
.privacy-section:hover {
      box-shadow: 0 8px 30px rgba(56, 189, 248, 0.08);
    }
.privacy-section h2 {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--main);
      margin-bottom: 1rem;
      border-left: 4px solid var(--accent);
      padding-left: 1rem;
    }
.privacy-section p, .privacy-section li {
      color: var(--text);
      line-height: 1.8;
      font-size: 0.98rem;
    }
.privacy-section ul {
      padding-left: 1.4rem;
      margin-top: 0.8rem;
    }
.privacy-section li {
      margin-bottom: 0.5rem;
    }
.privacy-meta {
      color: var(--muted);
      font-size: 0.85rem;
      border-bottom: 1px dashed var(--border-color);
      padding-bottom: 1rem;
      margin-bottom: 1.8rem;
      display: flex;
      gap: 1.5rem;
      flex-wrap: wrap;
    }
.highlight-badge {
      background: rgba(167, 139, 250, 0.15);
      color: var(--accent);
      border-radius: 50px;
      padding: 0.2rem 1rem;
      font-weight: 600;
      font-size: 0.85rem;
      display: inline-block;
      margin-right: 0.5rem;
      border: 1px solid rgba(167, 139, 250, 0.3);
    }
.effective-date {
      background: rgba(56, 189, 248, 0.1);
      border-radius: 30px;
      padding: 0.15rem 0.9rem;
      color: var(--main);
      font-weight: 500;
    }
.footer-ym a {
      color: var(--muted);
    }
.footer-ym a:hover {
      color: var(--main);
    }

/* --- Bootstrap 组件配色适配(程序自动补,避免白底黑字) --- */
.accordion-header { background:transparent !important; }