:root {
    --m-primary: #64748b;
    --m-accent: #94a3b8;
    --m-bg: #f1f5f9;
    --m-text: #1e293b;
    --m-radius: 8px;
    --m-border: #d7dee8;
    --m-shadow: 0 1px 4px rgba(30, 41, 59, 0.04), 0 4px 12px rgba(30, 41, 59, 0.03);
    --m-font-title: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
    --m-font-body: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  }

  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }

  body {
    background-color: var(--m-bg);
    color: var(--m-text);
    font-family: var(--m-font-body);
    line-height: 1.75;
    font-weight: 400;
    -webkit-font-smoothing: antialiased;
  }

  /* 细微噪点纹理叠加在顶部 */
  body::before {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 9999;
    opacity: 0.03;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 250 250' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
  }

  /* 阅读进度条 */
  #reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: var(--m-primary);
    z-index: 99999;
    transition: width 0.1s linear;
    border-radius: 0 2px 2px 0;
  }

  h1, h2, h3, h4, .navbar-brand {
    font-family: var(--m-font-title);
    letter-spacing: -0.01em;
    font-weight: 600;
  }

  a {
    color: var(--m-primary);
    text-decoration: none;
  }
  a:hover {
    color: #475569;
  }

  /* 布局: 左侧固定侧栏 + 右侧内容 */
  .layout-wrapper {
    display: flex;
    width: 100%;
    max-width: 1440px;
    margin: 0 auto;
    gap: 0;
  }

  /* 左侧侧栏 (固定) */
  .sidebar-left {
    width: 260px;
    flex-shrink: 0;
    background: rgba(255,255,255,0.5);
    backdrop-filter: blur(8px);
    border-right: 1px solid var(--m-border);
    padding: 2rem 1.5rem;
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    z-index: 5;
  }

  .sidebar-logo {
    font-size: 1.8rem;
    font-weight: 800;
    color: var(--m-text);
    display: flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 2rem;
    border-bottom: 1px solid var(--m-border);
    padding-bottom: 1.5rem;
  }
  .sidebar-logo i {
    color: var(--m-primary);
    font-size: 1.4rem;
  }

  .sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    list-style: none;
    padding-left: 0;
  }
  .sidebar-nav .nav-item {
    width: 100%;
  }
  .sidebar-nav .nav-link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 0.6rem 0.8rem;
    border-radius: var(--m-radius);
    font-weight: 500;
    color: var(--m-text);
    transition: 0.2s;
  }
  .sidebar-nav .nav-link i {
    width: 20px;
    text-align: center;
    color: var(--m-primary);
  }
  .sidebar-nav .nav-link:hover, .sidebar-nav .nav-link.active {
    background: rgba(100,116,139,0.08);
    color: var(--m-primary);
  }

  .sidebar-faq-mini {
    margin-top: auto;
    font-size: 0.85rem;
    color: var(--m-accent);
    border-top: 1px solid var(--m-border);
    padding-top: 1.2rem;
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
  }
  .sidebar-faq-mini a {
    color: var(--m-text);
    opacity: 0.7;
    transition: 0.2s;
  }
  .sidebar-faq-mini a:hover {
    opacity: 1;
  }

  /* 右侧主内容 */
  .main-content {
    flex: 1;
    min-width: 0;
    padding: 2rem 2.5rem;
  }

  /* 顶部导航 (移动端显示, 隐藏侧栏) */
  .mobile-topbar {
    display: none;
    width: 100%;
    background: rgba(255,255,255,0.75);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--m-border);
    padding: 1rem 1.5rem;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 1000;
  }
  .mobile-brand {
    font-size: 1.4rem;
    font-weight: 800;
    color: var(--m-text);
    display: flex;
    align-items: center;
    gap: 6px;
  }
  .btn-collapse {
    background: none;
    border: 1px solid var(--m-border);
    padding: 0.4rem 0.8rem;
    border-radius: var(--m-radius);
    color: var(--m-primary);
    font-size: 1.2rem;
  }
  .mobile-nav-collapse {
    width: 100%;
    display: none;
    flex-direction: column;
    padding: 1rem 0;
  }
  .mobile-nav-collapse.show {
    display: flex;
  }
  .mobile-nav-collapse a {
    padding: 0.5rem 0.8rem;
    border-radius: var(--m-radius);
    font-weight: 500;
  }

  /* Hero */
  .hero-section {
    position: relative;
    border-radius: 12px;
    overflow: hidden;
    margin-bottom: 2.5rem;
    background: linear-gradient(135deg, #1e293b 0%, #3b4a5f 100%);
    min-height: 300px;
    display: flex;
    align-items: center;
    box-shadow: var(--m-shadow);
  }
  .hero-bg-img {
    position: absolute;
    inset: 0;
    background-image: url('{随机图片}');
    background-size: cover;
    background-position: center;
    opacity: 0.4;
  }
  .hero-content {
    position: relative;
    z-index: 2;
    padding: 3rem 2.5rem;
    color: white;
    max-width: 70%;
  }
  .hero-content h1 {
    font-size: 2.8rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 1rem;
    text-shadow: 0 4px 18px rgba(0,0,0,0.3);
  }
  .hero-content p {
    font-size: 1.1rem;
    opacity: 0.9;
    text-shadow: 0 2px 8px rgba(0,0,0,0.2);
  }

  /* 通用卡片 */
  .section-title {
    font-weight: 700;
    font-size: 1.7rem;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 8px;
  }
  .section-title i {
    color: var(--m-primary);
    font-size: 1.4rem;
  }

  .card-flat {
    background: rgba(255,255,255,0.75);
    backdrop-filter: blur(4px);
    border: 1px solid var(--m-border);
    border-radius: var(--m-radius);
    box-shadow: var(--m-shadow);
  }

  /* 数据统计 */
  .stat-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
    margin-bottom: 2rem;
  }
  .stat-item {
    padding: 1.2rem 1rem;
    text-align: center;
  }
  .stat-number {
    font-size: 2rem;
    font-weight: 800;
    color: var(--m-primary);
  }
  .stat-label {
    font-size: 0.9rem;
    opacity: 0.7;
  }

  /* 使用说明 - 手风琴 */
  .accordion-custom .accordion-item {
    background: rgba(255,255,255,0.5);
    border: 1px solid var(--m-border);
    border-radius: var(--m-radius) !important;
    margin-bottom: 0.8rem;
    overflow: hidden;
  }
  .accordion-custom .accordion-button {
    background: rgba(255,255,255,0.4);
    font-weight: 600;
    color: var(--m-text);
    padding: 1rem 1.25rem;
    box-shadow: none;
  }
  .accordion-custom .accordion-button:not(.collapsed) {
    color: var(--m-primary);
    background: rgba(100,116,139,0.05);
  }
  .accordion-custom .accordion-body {
    padding: 0.8rem 1.25rem 1.2rem;
  }

  /* 特色 - 图标列表 */
  .feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 1.2rem;
    margin-bottom: 2rem;
  }
  .feature-card {
    padding: 1.5rem 1rem;
    text-align: left;
    transition: 0.2s;
  }
  .feature-card i {
    font-size: 2rem;
    color: var(--m-primary);
    margin-bottom: 0.7rem;
    display: inline-block;
  }
  .feature-card h5 {
    font-weight: 600;
    margin-bottom: 0.4rem;
  }
  .feature-card p {
    font-size: 0.9rem;
    opacity: 0.75;
    margin-bottom: 0;
  }

  /* FAQ 区块 */
  .faq-grid {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
    margin-bottom: 2rem;
  }

  /* CTA */
  .cta-box {
    background: linear-gradient(145deg, rgba(100,116,139,0.1), rgba(148,163,178,0.1));
    border: 1px dashed var(--m-primary);
    padding: 2.5rem;
    text-align: center;
    border-radius: 16px;
    margin-top: 1rem;
  }
  .cta-box h3 {
    font-weight: 700;
    margin-bottom: 0.8rem;
  }

  /* 友情链接 & 页脚 */
  .friend-links {
    background: rgba(255,255,255,0.35);
    border-radius: 12px;
    padding: 1.5rem 1.8rem;
    margin-top: 3rem;
  }
  .friend-links h6 {
    font-weight: 600;
    letter-spacing: 0.3px;
  }
  footer {
    padding: 1.8rem 0 2rem;
    color: var(--m-accent);
    font-size: 0.9rem;
    border-top: 1px solid var(--m-border);
    margin-top: 2rem;
    text-align: center;
  }

  /* 滚动动效 */
  .reveal {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s cubic-bezier(0.2, 0.7, 0.3, 1), transform 0.5s cubic-bezier(0.2, 0.7, 0.3, 1);
  }
  .reveal.in-view {
    opacity: 1;
    transform: translateY(0);
  }

  /* hover播放按钮 */
  .poster-hover {
    position: relative;
    overflow: hidden;
    border-radius: var(--m-radius);
    aspect-ratio: 4 / 3;
    background: #e2e8f0;
    margin-bottom: 0.8rem;
    background-image: url('{随机图片}');
    background-size: cover;
    background-position: center;
    transition: 0.2s;
  }
  .play-overlay {
    position: absolute;
    inset: 0;
    background: rgba(30, 41, 59, 0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: 0.2s;
    color: white;
    font-size: 2.5rem;
    backdrop-filter: blur(2px);
  }
  .poster-hover:hover .play-overlay {
    opacity: 1;
  }

  /* 响应式 */
  @media (max-width: 992px) {
    .sidebar-left {
      display: none;
    }
    .mobile-topbar {
      display: flex;
      flex-wrap: wrap;
    }
    .main-content {
      padding: 1.5rem 1rem;
    }
    .hero-content {
      max-width: 100%;
      padding: 2rem;
    }
    .hero-content h1 {
      font-size: 2rem;
    }
    .stat-grid {
      grid-template-columns: repeat(2, 1fr);
    }
  }
  @media (max-width: 576px) {
    .hero-content h1 {
      font-size: 1.7rem;
    }
    .feature-grid {
      grid-template-columns: 1fr;
    }
    .stat-grid {
      grid-template-columns: 1fr 1fr;
    }
  }

/* --- 子页面追加 --- */
/* 本页专属样式 */
        .about-hero {
            padding: 48px 0 32px;
        }
.about-hero h1 {
            font-size: 2.2rem;
            font-weight: 800;
            color: var(--m-text);
            margin-bottom: 12px;
            letter-spacing: -0.02em;
        }
.about-hero .lead {
            font-size: 1.05rem;
            color: var(--m-primary);
            max-width: 680px;
            line-height: 1.7;
        }
.about-section {
            margin-top: 40px;
        }
.about-section .section-title {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--m-text);
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid var(--m-accent);
            display: inline-block;
        }
.about-section p {
            color: var(--m-text);
            line-height: 1.8;
            margin-bottom: 16px;
            font-size: 0.95rem;
        }
.about-section ul {
            padding-left: 20px;
            margin-bottom: 16px;
        }
.about-section li {
            color: var(--m-text);
            line-height: 1.8;
            font-size: 0.95rem;
            margin-bottom: 6px;
        }
.timeline-item {
            position: relative;
            padding-left: 24px;
            margin-bottom: 20px;
            border-left: 2px solid var(--m-accent);
        }
.timeline-item .year {
            font-weight: 700;
            color: var(--m-primary);
            font-size: 0.95rem;
        }
.timeline-item p {
            margin-top: 4px;
            margin-bottom: 0;
        }
.value-card {
            background: #ffffff;
            border: 1px solid var(--m-border);
            border-radius: var(--m-radius);
            padding: 20px;
            margin-bottom: 16px;
            box-shadow: var(--m-shadow);
            transition: transform 0.2s ease, box-shadow 0.2s ease;
        }
.value-card:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 16px rgba(30, 41, 59, 0.08);
        }
.value-card .icon {
            font-size: 1.5rem;
            color: var(--m-primary);
            margin-bottom: 10px;
        }
.value-card h3 {
            font-size: 1.1rem;
            font-weight: 700;
            color: var(--m-text);
            margin-bottom: 8px;
        }
.value-card p {
            font-size: 0.9rem;
            color: var(--m-primary);
            margin-bottom: 0;
            line-height: 1.6;
        }
.stat-box {
            background: var(--m-bg);
            border: 1px solid var(--m-border);
            border-radius: var(--m-radius);
            padding: 16px 20px;
            text-align: center;
            margin-bottom: 12px;
        }
.stat-box .num {
            font-size: 1.8rem;
            font-weight: 800;
            color: var(--m-text);
        }
.stat-box .label {
            font-size: 0.85rem;
            color: var(--m-primary);
            margin-top: 4px;
        }

/* --- 子页面追加 --- */
/* 本页专属样式 */
        .legal-section {
            margin-bottom: 2.5rem;
        }
.legal-section h2 {
            font-size: 1.3rem;
            font-weight: 700;
            color: var(--m-text);
            border-left: 4px solid var(--m-accent);
            padding-left: 1rem;
            margin-bottom: 1.2rem;
        }
.legal-section p {
            color: var(--m-text);
            opacity: .85;
            line-height: 1.8;
            margin-bottom: .9rem;
            font-size: .95rem;
        }
.legal-section ul {
            padding-left: 1.5rem;
            color: var(--m-text);
            opacity: .85;
            line-height: 1.8;
            font-size: .95rem;
        }
.legal-section li {
            margin-bottom: .5rem;
        }
.legal-date {
            display: inline-block;
            background: var(--m-accent);
            color: var(--m-bg);
            padding: .2rem .9rem;
            border-radius: 20px;
            font-size: .8rem;
            font-weight: 600;
            margin-top: .5rem;
        }
.legal-note {
            background: rgba(100, 116, 139, .06);
            border: 1px solid var(--m-border);
            border-radius: var(--m-radius);
            padding: 1.2rem 1.4rem;
            font-size: .9rem;
            color: var(--m-text);
            opacity: .9;
            margin-top: 1.5rem;
        }
.legal-note i {
            color: var(--m-accent);
            margin-right: .5rem;
        }

/* --- 子页面追加 --- */
/* 排行榜专属微调，沿用CSS变量，保证风格一致 */
        .rank-table { width: 100%; border-collapse: collapse; margin-top: 1.2rem; }
.rank-table th { font-family: var(--m-font-title); font-weight: 600; color: var(--m-primary); text-align: left; padding: 0.8rem 0.5rem; border-bottom: 2px solid var(--m-border); font-size: 0.95rem; letter-spacing: 0.3px; }
.rank-table td { padding: 0.9rem 0.5rem; border-bottom: 1px solid var(--m-border); vertical-align: middle; }
.rank-badge { display: inline-flex; align-items: center; justify-content: center; width: 30px; height: 30px; border-radius: 8px; background: var(--m-bg); color: var(--m-primary); font-weight: 700; font-size: 0.9rem; margin-right: 10px; border: 1px solid var(--m-border); }
.rank-badge.top1 { background: #f59e0b; color: white; border-color: #f59e0b; }
.rank-badge.top2 { background: #94a3b8; color: white; border-color: #94a3b8; }
.rank-badge.top3 { background: #b45309; color: white; border-color: #b45309; }
.rank-title { font-weight: 600; color: var(--m-text); }
.rank-tag { display: inline-block; background: rgba(100,116,139,0.12); color: var(--m-primary); font-size: 0.75rem; padding: 2px 10px; border-radius: 30px; margin-left: 10px; font-weight: 500; }
.rank-score { font-family: var(--m-font-title); font-weight: 700; color: var(--m-accent); }
.trend-up { color: #16a34a; font-size: 0.8rem; margin-left: 4px; }
.trend-down { color: #dc2626; font-size: 0.8rem; margin-left: 4px; }
.trend-flat { color: var(--m-accent); font-size: 0.8rem; margin-left: 4px; }
.rank-note { font-size: 0.85rem; color: var(--m-accent); line-height: 1.6; }
.rank-category { font-size: 0.75rem; background: var(--m-bg); padding: 2px 8px; border-radius: 4px; color: var(--m-primary); border: 1px solid var(--m-border); margin-right: 6px; white-space: nowrap; }
.friend-links a { margin-right: 1.2rem; }
/* 覆盖bootstrap组件颜色，确保深色一致（此处仅使用栅格，但保险起见） */
        .card, .card-body { background: var(--m-bg); color: var(--m-text); border-color: var(--m-border); }
.list-group-item { background: var(--m-bg); color: var(--m-text); border-color: var(--m-border); }

/* --- 子页面追加 --- */
/* 本页专属补充样式 */
        .join-hero {
            background: linear-gradient(135deg, var(--m-primary) 0%, #475569 100%);
            color: #fff;
            padding: 60px 0 50px;
            border-radius: 0 0 24px 24px;
            position: relative;
            overflow: hidden;
        }
.join-hero::after {
            content: '';
            position: absolute;
            top: -30%;
            right: -10%;
            width: 400px;
            height: 400px;
            background: rgba(255,255,255,0.06);
            border-radius: 50%;
        }
.join-hero h1 {
            font-family: var(--m-font-title);
            font-weight: 800;
            font-size: 2.2rem;
            position: relative;
            z-index: 1;
        }
.join-hero p {
            font-size: 1.05rem;
            opacity: 0.9;
            max-width: 600px;
            position: relative;
            z-index: 1;
        }
.join-card {
            background: #fff;
            border-radius: var(--m-radius);
            border: 1px solid var(--m-border);
            box-shadow: var(--m-shadow);
            padding: 28px;
            height: 100%;
            transition: transform .2s ease, box-shadow .2s ease;
        }
.join-card:hover {
            transform: translateY(-4px);
            box-shadow: 0 8px 24px rgba(30, 41, 59, 0.10);
        }
.join-card .icon-circle {
            width: 56px;
            height: 56px;
            border-radius: 50%;
            background: var(--m-bg);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.4rem;
            color: var(--m-primary);
            margin-bottom: 16px;
        }
.join-card h3 {
            font-family: var(--m-font-title);
            font-weight: 700;
            font-size: 1.1rem;
            color: var(--m-text);
            margin-bottom: 10px;
        }
.join-card p {
            color: #64748b;
            font-size: .92rem;
            line-height: 1.6;
            margin-bottom: 0;
        }
.steps-section {
            padding: 50px 0 20px;
        }
.step-item {
            display: flex;
            gap: 16px;
            margin-bottom: 28px;
        }
.step-num {
            flex-shrink: 0;
            width: 36px;
            height: 36px;
            border-radius: 50%;
            background: var(--m-primary);
            color: #fff;
            font-weight: 700;
            font-size: .95rem;
            display: flex;
            align-items: center;
            justify-content: center;
            font-family: var(--m-font-title);
        }
.step-content h4 {
            font-family: var(--m-font-title);
            font-weight: 600;
            font-size: 1rem;
            color: var(--m-text);
            margin-bottom: 6px;
        }
.step-content p {
            color: #64748b;
            font-size: .9rem;
            line-height: 1.6;
            margin-bottom: 0;
        }
.benefit-list {
            list-style: none;
            padding: 0;
            margin: 0;
        }
.benefit-list li {
            padding: 10px 0;
            border-bottom: 1px dashed var(--m-border);
            display: flex;
            gap: 10px;
            align-items: flex-start;
            font-size: .92rem;
            color: var(--m-text);
        }
.benefit-list li:last-child {
            border-bottom: none;
        }
.benefit-list i {
            color: var(--m-primary);
            margin-top: 3px;
            font-size: .85rem;
        }
.cta-panel {
            background: var(--m-bg);
            border: 1px solid var(--m-border);
            border-radius: 12px;
            padding: 32px;
            text-align: center;
            margin: 40px 0;
        }
.btn-join {
            display: inline-block;
            background: var(--m-primary);
            color: #fff;
            padding: 12px 36px;
            border-radius: 50px;
            font-weight: 600;
            font-family: var(--m-font-title);
            text-decoration: none;
            transition: background .2s, transform .2s;
            border: none;
            font-size: 1rem;
        }
.btn-join:hover {
            background: #334155;
            color: #fff;
            transform: translateY(-2px);
        }
.btn-ghost {
            display: inline-block;
            background: transparent;
            color: var(--m-primary);
            padding: 10px 30px;
            border-radius: 50px;
            font-weight: 600;
            font-family: var(--m-font-title);
            text-decoration: none;
            border: 2px solid var(--m-primary);
            transition: all .2s;
            margin-left: 12px;
            font-size: 1rem;
        }
.btn-ghost:hover {
            background: var(--m-primary);
            color: #fff;
        }
.join-hero {
                padding: 40px 0 36px;
            }
.join-hero h1 {
                font-size: 1.6rem;
            }
.cta-panel {
                padding: 24px 16px;
            }
.btn-ghost {
                margin-left: 0;
                margin-top: 10px;
            }

/* --- Bootstrap 组件配色适配(程序自动补,避免白底黑字) --- */
.form-control { background:#fff !important; color:#1e293b !important; border-color:rgba(0,0,0,.12) !important; }
.form-label { color:#1e293b !important; }
.accordion-header { background:transparent !important; }
.form-control::placeholder { color: rgba(0,0,0,.4) !important; }