/* roulang page: index */
:root {
      --primary: #8B5CF6;
      --primary-light: #A855F7;
      --accent-cyan: #06B6D4;
      --accent-orange: #F97316;
      --bg-dark: #0F0F1A;
      --bg-card: rgba(15, 15, 26, 0.6);
      --text-primary: #F8FAFC;
      --text-secondary: #CBD5E1;
      --text-muted: #94A3B8;
      --border-subtle: rgba(255, 255, 255, 0.08);
      --border-active: rgba(139, 92, 246, 0.5);
      --shadow-card: 0 20px 35px -12px rgba(0,0,0,0.55);
      --radius-xl: 24px;
      --radius-2xl: 28px;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
      background-color: var(--bg-dark);
      color: var(--text-primary);
      line-height: 1.7;
      margin: 0;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    @media (min-width: 768px) {
      .container {
        padding-left: 2.5rem;
        padding-right: 2.5rem;
      }
    }

    /* 导航与毛玻璃效果 */
    .navbar {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(10, 10, 20, 0.8);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid var(--border-subtle);
    }

    .logo-text {
      background: linear-gradient(135deg, #A855F7, #06B6D4);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      font-weight: 800;
      letter-spacing: -0.02em;
    }

    .nav-link {
      transition: color 0.2s, background 0.2s;
      color: #CBD5E1;
      font-weight: 500;
      border-radius: 2rem;
      padding: 0.4rem 1rem;
    }
    .nav-link:hover {
      color: #A855F7;
      background: rgba(139, 92, 246, 0.1);
    }

    .btn-primary {
      background: linear-gradient(135deg, #8B5CF6, #06B6D4);
      color: white;
      font-weight: 700;
      padding: 0.7rem 1.8rem;
      border-radius: 9999px;
      box-shadow: 0 8px 20px -6px rgba(139, 92, 246, 0.5);
      transition: all 0.25s ease;
      border: none;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }
    .btn-primary:hover {
      box-shadow: 0 12px 28px -4px rgba(6, 182, 212, 0.6);
      transform: scale(1.04);
      background: linear-gradient(135deg, #9D6CFF, #22D3EE);
    }

    .btn-outline {
      border: 2px solid rgba(168, 85, 247, 0.6);
      color: #C4B5FD;
      font-weight: 600;
      padding: 0.7rem 1.8rem;
      border-radius: 9999px;
      background: transparent;
      transition: all 0.25s;
    }
    .btn-outline:hover {
      background: rgba(168, 85, 247, 0.15);
      border-color: #A855F7;
      color: #E9D5FF;
    }

    .card-hover {
      transition: transform 0.25s ease, box-shadow 0.3s;
      background: rgba(15, 15, 30, 0.65);
      backdrop-filter: blur(16px);
      border: 1px solid rgba(255, 255, 255, 0.07);
      border-radius: var(--radius-2xl);
      box-shadow: 0 15px 25px -10px rgba(0,0,0,0.4);
    }
    .card-hover:hover {
      transform: translateY(-10px);
      box-shadow: 0 30px 45px -15px rgba(139, 92, 246, 0.35);
      border-color: rgba(139, 92, 246, 0.3);
    }

    .data-badge {
      background: linear-gradient(135deg, rgba(6, 182, 212, 0.2), rgba(168, 85, 247, 0.25));
      border: 1px solid rgba(6, 182, 212, 0.45);
      border-radius: 2rem;
      padding: 0.2rem 1rem;
      font-weight: 700;
      display: inline-flex;
      align-items: center;
      gap: 0.3rem;
      backdrop-filter: blur(8px);
      font-size: 0.9rem;
      color: #CFFAFE;
    }

    .section-title {
      font-size: 2.3rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      margin-bottom: 1rem;
      display: inline-block;
      position: relative;
    }
    .section-title::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -10px;
      width: 65%;
      height: 4px;
      background: linear-gradient(90deg, #8B5CF6, #06B6D4);
      border-radius: 4px;
    }

    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.06);
    }
    .faq-question {
      cursor: pointer;
      font-weight: 600;
      padding: 1.2rem 0;
      display: flex;
      align-items: center;
      gap: 1rem;
      color: #F1F5F9;
      transition: 0.2s;
    }
    .faq-question:hover {
      color: #C4B5FD;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s;
      color: #CBD5E1;
      padding-left: 2.2rem;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 1.2rem;
    }
    .faq-item.active .faq-question {
      color: #A855F7;
    }

    @media (max-width: 768px) {
      .mobile-menu {
        display: none;
        flex-direction: column;
        background: rgba(10,10,25,0.95);
        backdrop-filter: blur(30px);
        position: absolute;
        top: 70px;
        left: 0;
        width: 100%;
        padding: 1.5rem;
        border-bottom: 1px solid rgba(255,255,255,0.05);
      }
      .mobile-menu.open {
        display: flex;
      }
    }

    .pulse-animation {
      animation: pulse-glow 2.5s infinite;
    }
    @keyframes pulse-glow {
      0% { box-shadow: 0 0 0 0 rgba(168,85,247,0.7); }
      70% { box-shadow: 0 0 0 15px rgba(168,85,247,0); }
      100% { box-shadow: 0 0 0 0 rgba(168,85,247,0); }
    }