/* roulang page: index */
:root {
      --primary: #0A4C7B;
      --primary-hover: #083B5E;
      --secondary: #1B7FA8;
      --accent: #F5A623;
      --accent-hover: #E09515;
      --bg-light: #F8FAFC;
      --card-bg: #FFFFFF;
      --text-primary: #1E293B;
      --text-secondary: #475569;
      --text-muted: #64748B;
      --border-light: #E2E8F0;
      --shadow-card: 0 4px 20px rgba(10,76,123,0.08);
      --shadow-hover: 0 8px 30px rgba(10,76,123,0.15);
      --radius-md: 12px;
      --radius-sm: 8px;
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-light);
      color: var(--text-primary);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }
    @media (max-width: 768px) {
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }
    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: #FFFFFF;
      box-shadow: 0 1px 4px rgba(0,0,0,0.04);
      z-index: 50;
      display: flex;
      align-items: center;
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .logo i {
      color: var(--accent);
      font-size: 1.8rem;
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      align-items: center;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding-bottom: 4px;
      transition: color 0.2s;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .nav-links a.active {
      color: var(--primary);
      font-weight: 600;
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent);
      border-radius: 2px;
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary);
      cursor: pointer;
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .menu-toggle {
        display: block;
      }
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(10,76,123,0.98);
      backdrop-filter: blur(6px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2rem;
      z-index: 100;
      transform: translateY(-100%);
      transition: transform 0.3s ease;
    }
    .mobile-menu.open {
      transform: translateY(0);
    }
    .mobile-menu a {
      color: white;
      font-size: 1.5rem;
      font-weight: 600;
      text-decoration: none;
    }
    .close-menu {
      position: absolute;
      top: 24px;
      right: 24px;
      background: none;
      border: none;
      color: white;
      font-size: 2rem;
      cursor: pointer;
    }
    /* 卡片 */
    .card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
      overflow: hidden;
    }
    .card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border-radius: var(--radius-sm);
      padding: 12px 28px;
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: background 0.2s;
      text-decoration: none;
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
    }
    .btn-accent {
      background: var(--accent);
      color: white;
      border-radius: var(--radius-sm);
      padding: 14px 32px;
      font-weight: 700;
      border: none;
      cursor: pointer;
      transition: background 0.2s;
      text-decoration: none;
      display: inline-block;
      box-shadow: 0 4px 12px rgba(245,166,35,0.3);
    }
    .btn-accent:hover {
      background: var(--accent-hover);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-sm);
      padding: 8px 20px;
      font-weight: 500;
      transition: all 0.2s;
      text-decoration: none;
      display: inline-block;
    }
    .btn-outline:hover {
      background: #E8F2F8;
      border-color: var(--primary-hover);
    }
    input, textarea {
      border: 1px solid #CBD5E1;
      border-radius: var(--radius-sm);
      padding: 12px 16px;
      width: 100%;
      font-size: 1rem;
      transition: border 0.2s, box-shadow 0.2s;
      outline: none;
    }
    input:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 4px rgba(10,76,123,0.15);
    }
    /* 对比表高亮 */
    .compare-highlight {
      border: 2px solid var(--primary);
      background: #F0F7FF;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      background: #F1F5F9;
      padding: 18px 24px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      transition: background 0.2s;
    }
    .faq-question:hover {
      background: #E8F2F8;
    }
    .faq-answer {
      padding: 0 24px;
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
      background: white;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 18px 24px;
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--accent);
    }