/* roulang page: index */
:root {
      --primary: #0F172A;
      --accent: #F97316;
      --bg: #F8FAFC;
      --card-bg: #FFFFFF;
      --text: #1E293B;
      --muted: #64748B;
      --border: #E2E8F0;
      --radius: 16px;
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
      --font-sans: "Inter", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: all 0.2s ease;
      font-weight: 600;
      border-radius: 8px;
    }
    .container {
      width: 100%;
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 20px;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
      display: flex;
      align-items: center;
      z-index: 50;
      border-bottom: 1px solid rgba(0,0,0,0.02);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .badge {
      background: #DC2626;
      color: white;
      font-size: 0.7rem;
      font-weight: 600;
      padding: 2px 10px;
      border-radius: 20px;
      letter-spacing: 1px;
      margin-left: 6px;
      animation: breath 2s infinite;
      display: inline-flex;
      align-items: center;
    }
    @keyframes breath {
      0% { opacity: 0.9; transform: scale(1); }
      50% { opacity: 1; transform: scale(1.06); }
      100% { opacity: 0.9; transform: scale(1); }
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      font-weight: 500;
      color: #334155;
    }
    .nav-links a:hover {
      color: var(--accent);
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      padding: 12px 28px;
      border-radius: 8px;
      font-weight: 600;
      box-shadow: 0 4px 10px rgba(249,115,22,0.3);
    }
    .btn-primary:hover {
      background: #EA580C;
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(249,115,22,0.4);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 10px 26px;
      border-radius: 8px;
      font-weight: 600;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    .hamburger {
      display: none;
      font-size: 28px;
      background: none;
      border: none;
      color: var(--primary);
    }
    .menu-panel {
      display: none;
    }
    @media (max-width: 768px) {
      .nav-links, .header .btn-primary.desktop-cta {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .menu-panel.active {
        display: flex;
        flex-direction: column;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        height: calc(100vh - 72px);
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(20px);
        align-items: center;
        justify-content: center;
        gap: 40px;
        font-size: 1.8rem;
        font-weight: 600;
        color: var(--primary);
        z-index: 40;
      }
      .menu-panel a {
        display: block;
      }
      .menu-panel .btn-primary {
        display: inline-flex;
        margin-top: 20px;
      }
    }
    section {
      padding: 80px 0;
      scroll-margin-top: 80px;
    }
    .hero {
      padding-top: 140px;
      padding-bottom: 100px;
      background: linear-gradient(135deg, rgba(15,23,42,0.78) 0%, rgba(15,23,42,0.88) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      color: white;
    }
    .card {
      background: var(--card-bg);
      border-radius: var(--radius);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      transition: all 0.25s ease;
      border: 1px solid transparent;
    }
    .card:hover {
      box-shadow: var(--shadow-md);
      border-color: var(--accent);
      transform: translateY(-4px);
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 700;
      color: var(--accent);
      line-height: 1.2;
    }
    .faq-item {
      border: 1px solid var(--border);
      border-radius: 12px;
      margin-bottom: 16px;
      background: white;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 700;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--primary);
    }
    .faq-answer {
      padding: 0 24px 20px;
      color: var(--muted);
      display: none;
      background: #F1F5F9;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    .faq-item.active {
      border-color: var(--accent);
    }
    footer {
      background: var(--primary);
      color: #CBD5E1;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
      h1 {
        font-size: 2.2rem !important;
      }
      h2 {
        font-size: 1.8rem !important;
      }
    }