/* roulang page: index */
:root {
      --bg-main: #070B14;
      --bg-secondary: #0D1527;
      --bg-card: rgba(19, 30, 54, 0.65);
      --accent-blue-start: #0066FF;
      --accent-blue-end: #00F0FF;
      --accent-emerald: #10B981;
      --border-cyan: rgba(0, 240, 255, 0.18);
      --text-main: #F1F5F9;
      --text-muted: #94A3B8;
    }

    body {
      background-color: var(--bg-main);
      color: var(--text-main);
      font-family: Inter, system-ui, -apple-system, PingFang SC, "Microsoft YaHei", sans-serif;
      overflow-x: hidden;
      line-height: 1.75;
    }

    .glass-card {
      background: var(--bg-card);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--border-cyan);
      box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.08);
      border-radius: 16px;
      transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    }

    .glass-card:hover {
      border-color: rgba(0, 240, 255, 0.4);
      transform: translateY(-4px);
      box-shadow: 0 12px 30px rgba(0, 102, 255, 0.18), inset 0 1px 0 rgba(255, 255, 255, 0.15);
    }

    .glow-btn-primary {
      background: linear-gradient(135deg, var(--accent-blue-start) 0%, var(--accent-blue-end) 100%);
      box-shadow: 0 0 25px rgba(0, 102, 255, 0.5);
      color: #FFFFFF;
      font-weight: 600;
      transition: all 0.3s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border-radius: 9999px;
    }

    .glow-btn-primary:hover {
      box-shadow: 0 0 35px rgba(0, 240, 255, 0.7);
      transform: scale(1.02);
    }

    .glow-btn-outline {
      border: 1px solid rgba(0, 240, 255, 0.4);
      color: #E2E8F0;
      background: rgba(13, 21, 39, 0.6);
      backdrop-filter: blur(8px);
      transition: all 0.3s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border-radius: 9999px;
    }

    .glow-btn-outline:hover {
      border-color: #00F0FF;
      background: rgba(0, 240, 255, 0.1);
      color: #FFFFFF;
    }

    .tech-gradient-text {
      background: linear-gradient(135deg, #FFFFFF 20%, #93C5FD 60%, #00F0FF 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease-out, opacity 0.3s ease;
      opacity: 0;
    }

    .faq-item.active .faq-content {
      max-height: 240px;
      opacity: 1;
    }

    .faq-item.active .faq-icon {
      transform: rotate(45deg);
      color: #00F0FF;
    }

    .nav-blur-bg {
      background: rgba(7, 11, 20, 0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0, 240, 255, 0.12);
    }