/* roulang page: index */
:root {
      --primary: #1A3C6E;
      --accent: #E85D3F;
      --bg: #F8FAFC;
      --card-bg: #FFFFFF;
      --text-dark: #0F172A;
      --text-mid: #475569;
      --border-light: #E2E8F0;
      --success-green: #0D9488;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.04), 0 4px 12px rgba(0,0,0,0.06);
      --shadow-hover: 0 6px 20px rgba(26,60,110,0.10);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --transition: 0.2s ease;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
      background-color: var(--bg);
      color: var(--text-dark);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
    }
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }
    @media (max-width: 640px) {
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }
    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: white;
      border-bottom: 1px solid var(--border-light);
      height: 68px;
      display: flex;
      align-items: center;
      box-shadow: 0 1px 4px rgba(0,0,0,0.02);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.3px;
      white-space: nowrap;
    }
    .nav-tabs {
      display: flex;
      gap: 6px;
      align-items: center;
      flex-wrap: wrap;
    }
    .nav-chip {
      padding: 8px 16px;
      border-radius: var(--radius-tag);
      font-size: 15px;
      font-weight: 500;
      color: var(--text-mid);
      background: transparent;
      transition: background var(--transition), color var(--transition);
      white-space: nowrap;
    }
    .nav-chip:hover {
      background: rgba(26,60,110,0.05);
      color: var(--primary);
    }
    .nav-chip.active {
      background: rgba(26,60,110,0.1);
      color: var(--primary);
      font-weight: 600;
    }
    .header-cta {
      background: var(--accent);
      color: white;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 15px;
      transition: background var(--transition);
      white-space: nowrap;
      border: none;
    }
    .header-cta:hover {
      background: #C94A2F;
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 28px;
      color: var(--primary);
      line-height: 1;
    }
    @media (max-width: 1024px) {
      .nav-tabs {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .header-cta {
        display: none;
      }
      .mobile-menu {
        display: none;
        position: absolute;
        top: 68px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 20px 24px;
        gap: 12px;
        border-bottom: 1px solid var(--border-light);
        box-shadow: var(--shadow-sm);
        z-index: 40;
      }
      .mobile-menu.open {
        display: flex;
      }
      .mobile-menu .nav-chip {
        width: fit-content;
      }
    }
    /* 卡片与按钮 */
    .card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: transform 0.25s ease, box-shadow 0.25s ease;
      overflow: hidden;
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      font-weight: 600;
      font-size: 16px;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      border: none;
      letter-spacing: 0.5px;
      transition: background var(--transition);
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      background: #C94A2F;
    }
    .btn-outline {
      background: transparent;
      color: var(--primary);
      border: 1.5px solid var(--primary);
      font-weight: 600;
      font-size: 16px;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      letter-spacing: 0.5px;
      transition: background var(--transition), color var(--transition);
      display: inline-block;
      text-align: center;
    }
    .btn-outline:hover {
      background: rgba(26,60,110,0.05);
    }
    .tag {
      background: #E2E8F0;
      color: #1E293B;
      font-size: 13px;
      font-weight: 500;
      padding: 4px 12px;
      border-radius: var(--radius-tag);
      display: inline-block;
      letter-spacing: 0.3px;
    }
    .accent-tag {
      background: rgba(232,93,63,0.08);
      color: var(--accent);
      font-weight: 600;
    }
    /* 瀑布流 */
    .masonry {
      column-count: 3;
      column-gap: 24px;
      orphans: 1;
      widows: 1;
    }
    .masonry-item {
      break-inside: avoid;
      margin-bottom: 24px;
    }
    @media (max-width: 1024px) {
      .masonry {
        column-count: 2;
      }
    }
    @media (max-width: 640px) {
      .masonry {
        column-count: 1;
      }
    }
    /* 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      width: 100%;
      background: none;
      border: none;
      text-align: left;
      padding: 20px 0;
      font-size: 16px;
      font-weight: 600;
      color: var(--text-dark);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      color: var(--text-mid);
      font-size: 15px;
      padding: 0 0;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }
    .faq-icon {
      font-size: 20px;
      color: var(--primary);
      transition: transform 0.2s;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    /* 对比卡片 */
    .compare-card {
      border-radius: var(--radius-card);
      padding: 32px;
      background: white;
      box-shadow: var(--shadow-sm);
    }
    .left-compare {
      background: #F1F5F9;
    }
    .right-compare {
      background: rgba(26,60,110,0.03);
      border-left: 4px solid var(--primary);
    }
    /* 数据数字 */
    .stat-number {
      font-size: 28px;
      font-weight: 700;
      color: var(--accent);
      line-height: 1.2;
    }
    .stat-label {
      font-size: 13px;
      color: var(--text-mid);
      font-weight: 500;
    }