/* roulang page: index */
:root {
      --primary: #6366F1;
      --accent: #06B6D4;
      --bg-light: #F8FAFC;
      --bg-dark: #0B0F19;
      --text-main: #0F172A;
      --text-muted: #334155;
      --text-sub: #64748B;
      --border-color: #E2E8F0;
      --radius-lg: 1rem;
      --radius-xl: 1.5rem;
      --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.04);
      --shadow-md: 0 10px 25px -5px rgba(15, 23, 42, 0.08);
      --shadow-glow: 0 0 25px rgba(99, 102, 241, 0.25);
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      background-color: var(--bg-light);
      color: var(--text-muted);
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      line-height: 1.8;
      overflow-x: hidden;
    }

    .glass-panel {
      background: rgba(255, 255, 255, 0.88);
      backdrop-filter: blur(12px);
      border: 1px solid rgba(226, 232, 240, 0.8);
    }

    .glass-dark {
      background: rgba(17, 24, 39, 0.75);
      backdrop-filter: blur(16px);
      border: 1px solid rgba(255, 255, 255, 0.08);
    }

    .btn-gradient {
      background: linear-gradient(135deg, #6366F1 0%, #4F46E5 50%, #06B6D4 100%);
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }

    .btn-gradient:hover {
      transform: translateY(-2px);
      box-shadow: 0 12px 24px -6px rgba(99, 102, 241, 0.45);
    }

    .btn-outline {
      border: 1px solid #CBD5E1;
      transition: all 0.25s ease;
    }

    .btn-outline:hover {
      border-color: #6366F1;
      color: #6366F1;
      background: #EEF2FF;
    }

    .badge-soft {
      background: #EEF2FF;
      color: #4F46E5;
      border: 1px solid rgba(99, 102, 241, 0.2);
    }

    details summary::-webkit-details-marker {
      display: none;
    }

    details[open] summary .faq-icon {
      transform: rotate(180deg);
    }