/* roulang page: index */
:root {
      --primary-bg: #0A0E27;
      --secondary-bg: #0F1328;
      --footer-bg: #070A1A;
      --accent-blue: #1E90FF;
      --accent-gold: #D4A843;
      --text-primary: #E0E6F0;
      --text-secondary: #8899AA;
      --text-muted: #556677;
      --card-bg: rgba(15, 25, 50, 0.55);
      --card-border: rgba(30, 144, 255, 0.2);
      --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
      --button-radius: 12px;
      --card-radius: 16px;
      --input-radius: 8px;
      --white: #FFFFFF;
      --nav-bg: #FFFFFF;
      --nav-text: #333333;
      --nav-border: #E5E8EB;
      --font-sans: -apple-system, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--primary-bg);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding-left: 24px;
      padding-right: 24px;
    }

    /* 导航系统：白底内容平台风格 */
    .site-header {
      background-color: var(--nav-bg);
      border-bottom: 1px solid var(--nav-border);
      box-shadow: 0 1px 8px rgba(0,0,0,0.06);
      height: 64px;
      position: sticky;
      top: 0;
      z-index: 100;
      width: 100%;
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 64px;
    }

    .logo-area {
      display: flex;
      align-items: center;
      gap: 10px;
      text-decoration: none;
      color: var(--primary-bg);
      font-weight: 700;
      font-size: 20px;
      letter-spacing: -0.3px;
    }

    .logo-icon {
      width: 32px;
      height: 32px;
      background: linear-gradient(135deg, var(--accent-blue), #0A0E27);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 18px;
    }

    .nav-links {
      display: flex;
      gap: 28px;
      list-style: none;
      margin: 0;
    }

    .nav-links a {
      color: var(--nav-text);
      font-size: 15px;
      font-weight: 500;
      text-decoration: none;
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-blue);
      border-bottom-color: var(--accent-blue);
    }

    .header-actions {
      display: flex;
      align-items: center;
      gap: 16px;
    }

    .search-box {
      display: flex;
      align-items: center;
      background: #f5f7fa;
      border: 1px solid #E0E0E0;
      border-radius: 20px;
      padding: 0 16px;
      height: 36px;
      transition: border 0.2s;
    }

    .search-box input {
      border: none;
      background: transparent;
      outline: none;
      font-size: 14px;
      width: 140px;
      color: var(--nav-text);
    }

    .search-box:focus-within {
      border-color: var(--accent-blue);
      box-shadow: 0 0 0 2px rgba(30,144,255,0.15);
    }

    .btn-nav-cta {
      background: var(--accent-blue);
      color: white;
      padding: 8px 20px;
      border-radius: 20px;
      font-weight: 600;
      font-size: 14px;
      text-decoration: none;
      transition: background 0.2s, box-shadow 0.2s;
      white-space: nowrap;
    }

    .btn-nav-cta:hover {
      background: #3AA5FF;
      box-shadow: 0 0 14px rgba(30,144,255,0.5);
      color: white;
    }

    .mobile-menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--nav-text);
      cursor: pointer;
    }

    /* Hero */
    .hero {
      background-color: var(--primary-bg);
      background-image: radial-gradient(circle at 30% 40%, rgba(30,144,255,0.08) 0%, transparent 60%);
      padding: 100px 0;
      position: relative;
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 40px;
    }

    .hero-content {
      flex: 1;
    }

    .hero h1 {
      font-size: 46px;
      font-weight: 700;
      letter-spacing: -0.02em;
      color: white;
      margin-bottom: 20px;
      line-height: 1.2;
    }

    .hero-sub {
      font-size: 17px;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 500px;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--accent-blue);
      color: white;
      padding: 14px 32px;
      border-radius: var(--button-radius);
      font-weight: 600;
      text-decoration: none;
      display: inline-block;
      box-shadow: 0 0 20px rgba(30,144,255,0.5);
      transition: all 0.25s;
      border: none;
      cursor: pointer;
    }

    .btn-primary:hover {
      background: #3AA5FF;
      box-shadow: 0 0 30px rgba(30,144,255,0.7);
      transform: scale(1.03);
      color: white;
    }

    .btn-gold {
      background: var(--accent-gold);
      color: #0A0E27;
      box-shadow: 0 0 24px rgba(212,168,67,0.5);
      font-weight: 700;
    }

    .btn-gold:hover {
      background: #e6b94d;
      box-shadow: 0 0 32px rgba(212,168,67,0.8);
      color: #0A0E27;
    }

    .btn-outline {
      background: transparent;
      border: 1px solid var(--accent-blue);
      color: var(--accent-blue);
      padding: 14px 32px;
      border-radius: var(--button-radius);
      font-weight: 600;
      text-decoration: none;
      transition: all 0.25s;
    }

    .btn-outline:hover {
      background: rgba(30,144,255,0.1);
      color: var(--accent-blue);
    }

    .hero-image {
      flex: 1;
      text-align: right;
    }

    .hero-image img {
      max-width: 100%;
      border-radius: 24px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.6);
    }

    /* 通用板块 */
    .section {
      padding: 90px 0;
    }

    .section-title {
      font-size: 32px;
      font-weight: 600;
      margin-bottom: 16px;
      color: white;
    }

    .section-sub {
      color: var(--text-secondary);
      margin-bottom: 48px;
      font-size: 17px;
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: blur(16px);
      border: 1px solid var(--card-border);
      border-radius: var(--card-radius);
      box-shadow: var(--card-shadow);
      padding: 28px;
      transition: transform 0.3s, box-shadow 0.3s;
      position: relative;
      overflow: hidden;
    }

    .glass-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 1px;
      background: rgba(255,255,255,0.04);
    }

    .glass-card:hover {
      transform: translateY(-6px);
      box-shadow: 0 16px 40px rgba(0,0,0,0.6);
      border-color: rgba(30,144,255,0.4);
    }

    .icon-circle {
      width: 48px;
      height: 48px;
      background: rgba(30,144,255,0.15);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent-blue);
      font-size: 24px;
      margin-bottom: 20px;
    }

    .card-title {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 10px;
    }

    .card-desc {
      color: var(--text-secondary);
      font-size: 15px;
    }

    /* 交替布局 */
    .feature-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 80px;
    }

    .feature-row.reverse {
      flex-direction: row-reverse;
    }

    .feature-text {
      flex: 1;
    }

    .feature-visual {
      flex: 1;
    }

    .feature-visual img {
      border-radius: 20px;
      width: 100%;
      box-shadow: 0 16px 32px rgba(0,0,0,0.5);
    }

    /* 数据卡 */
    .stats-grid {
      display: flex;
      justify-content: space-around;
      gap: 24px;
      flex-wrap: wrap;
    }

    .stat-item {
      text-align: center;
    }

    .stat-number {
      font-size: 40px;
      font-weight: 700;
      color: var(--accent-gold);
      font-family: 'Inter', sans-serif;
    }

    /* FAQ */
    .faq-item {
      margin-bottom: 12px;
    }

    .faq-question {
      background: var(--card-bg);
      backdrop-filter: blur(16px);
      border: 1px solid var(--card-border);
      border-radius: var(--card-radius);
      padding: 18px 24px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .faq-answer {
      padding: 0 24px 20px;
      color: var(--text-secondary);
      display: none;
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    /* CTA 区域 */
    .cta-section {
      background: var(--secondary-bg);
      padding: 80px 0;
      text-align: center;
    }

    .footer {
      background: var(--footer-bg);
      border-top: 1px solid rgba(30,144,255,0.1);
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }

    .footer h4 {
      color: var(--text-primary);
      font-size: 15px;
      margin-bottom: 16px;
    }

    .footer a {
      color: var(--text-secondary);
      text-decoration: none;
      font-size: 14px;
      display: block;
      margin-bottom: 8px;
    }

    .footer a:hover {
      color: var(--accent-blue);
    }

    .copyright {
      color: var(--text-muted);
      font-size: 13px;
      margin-top: 40px;
      border-top: 1px solid rgba(255,255,255,0.05);
      padding-top: 20px;
    }

    @media (max-width: 1024px) {
      .nav-links, .header-actions .search-box {
        display: none;
      }
      .mobile-menu-toggle {
        display: block;
      }
      .hero-grid {
        flex-direction: column;
      }
      .feature-row {
        flex-direction: column;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 640px) {
      .hero h1 {
        font-size: 32px;
      }
      .section-title {
        font-size: 26px;
      }
      .stats-grid {
        flex-direction: column;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }