/* roulang page: index */
:root {
      --primary: #00E5FF;
      --primary-glow: rgba(0, 229, 255, 0.5);
      --dark-bg: #0B0E14;
      --gold: #FFB300;
      --silver: #B0BEC5;
      --white: #FFFFFF;
      --gray-light: #F8FAFC;
      --border-light: #e2e8f0;
      --radius-lg: 1.5rem;
      --radius-md: 1rem;
      --shadow-card: 0 10px 25px -5px rgba(0,0,0,0.05), 0 8px 10px -6px rgba(0,0,0,0.02);
      --shadow-hover: 0 20px 35px -10px rgba(0,229,255,0.15), 0 10px 15px -8px rgba(0,0,0,0.05);
      --font-sans: 'Inter', 'SF Pro Display', -apple-system, 'Microsoft YaHei', sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      margin: 0;
      padding: 0;
      background-color: var(--white);
      color: #1e293b;
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      background: rgba(255,255,255,0.8);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(226,232,240,0.6);
      transition: background 0.3s;
    }
    .navbar.scrolled {
      background: rgba(255,255,255,1);
      box-shadow: 0 2px 8px rgba(0,0,0,0.02);
    }
    .nav-logo {
      display: flex;
      align-items: center;
      gap: 0.5rem;
      font-weight: 800;
      font-size: 1.5rem;
      color: #0B0E14;
    }
    .nav-logo i {
      color: var(--primary);
      font-size: 1.8rem;
    }
    .nav-link {
      font-weight: 500;
      color: #334155;
      padding: 0.5rem 0.75rem;
      border-radius: 0.5rem;
      transition: color 0.2s, background 0.2s;
    }
    .nav-link:hover {
      color: #00E5FF;
      background: rgba(0,229,255,0.05);
    }
    .search-box {
      display: flex;
      align-items: center;
      background: #f1f5f9;
      border-radius: 999px;
      padding: 0.4rem 1rem;
      gap: 0.5rem;
    }
    .search-box input {
      border: none;
      background: transparent;
      outline: none;
      font-size: 0.9rem;
      width: 160px;
    }
    .btn-primary {
      background: var(--primary);
      color: #0B0E14;
      font-weight: 700;
      padding: 0.65rem 1.8rem;
      border-radius: 999px;
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
      transition: all 0.25s;
      box-shadow: 0 4px 12px rgba(0,229,255,0.25);
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      background: #00d4f0;
      box-shadow: 0 0 22px rgba(0,229,255,0.6);
      transform: translateY(-1px);
    }
    .btn-outline {
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 700;
      padding: 0.65rem 1.8rem;
      border-radius: 999px;
      background: transparent;
      transition: all 0.25s;
    }
    .btn-outline:hover {
      background: rgba(0,229,255,0.08);
      box-shadow: 0 0 16px rgba(0,229,255,0.3);
    }
    .mobile-menu {
      display: none;
    }
    /* 区块间距 */
    section {
      padding-top: 5rem;
      padding-bottom: 5rem;
    }
    @media (min-width: 768px) {
      section {
        padding-top: 6rem;
        padding-bottom: 6rem;
      }
    }
    /* 卡片 */
    .card {
      background: white;
      border-radius: var(--radius-lg);
      padding: 2rem;
      box-shadow: var(--shadow-card);
      border: 1px solid var(--border-light);
      transition: transform 0.2s, box-shadow 0.3s;
    }
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid #e9eef2;
    }
    .faq-question {
      width: 100%;
      background: transparent;
      border: none;
      text-align: left;
      font-weight: 600;
      font-size: 1.1rem;
      padding: 1.2rem 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: #0f172a;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.3s;
      color: #475569;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding-bottom: 1.2rem;
    }
    .faq-item.open .faq-icon {
      transform: rotate(45deg);
    }
    .faq-icon {
      font-size: 1.5rem;
      color: #00E5FF;
      transition: transform 0.3s;
    }
    /* 深色数据区 */
    .dark-stats {
      background: #0B0E14;
      color: white;
    }
    .stat-number {
      font-size: 3.2rem;
      font-weight: 800;
      color: #FFB300;
      line-height: 1.2;
    }
    @media (max-width: 768px) {
      .nav-menu {
        display: none;
      }
      .mobile-menu {
        display: block;
      }
      .stat-number {
        font-size: 2.4rem;
      }
    }
    .scene-scroll {
      display: flex;
      gap: 1.5rem;
      overflow-x: auto;
      padding-bottom: 1rem;
      scroll-snap-type: x mandatory;
    }
    .scene-card {
      min-width: 220px;
      border-radius: 1.5rem;
      overflow: hidden;
      background: white;
      box-shadow: 0 8px 20px rgba(0,0,0,0.04);
      scroll-snap-align: start;
    }
    footer {
      background: #0B0E14;
      color: #B0BEC5;
    }
    footer a:hover {
      color: #00E5FF;
    }