/* roulang page: index */
:root {
      --primary: #0F172A;
      --primary-light: #1E293B;
      --accent: #0284C7;
      --accent-hover: #0369A1;
      --amber: #D97706;
      --amber-hover: #B45309;
      --bg-soft: #F8FAFC;
      --bg-alt: #F1F5F9;
      --text-main: #0F172A;
      --text-body: #334155;
      --text-muted: #64748B;
      --border-color: #E2E8F0;
    }

    html {
      scroll-behavior: smooth;
      font-family: system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    }

    body {
      color: var(--text-body);
      background-color: #FFFFFF;
      line-height: 1.75;
      overflow-x: hidden;
    }

    .glass-nav {
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 3px rgba(0,0,0,0.06);
    }

    .card-hover {
      transition: all 0.28s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .card-hover:hover {
      transform: translateY(-5px);
      box-shadow: 0 16px 30px -10px rgba(15, 23, 42, 0.1);
    }

    .hero-mask {
      background: linear-gradient(135deg, rgba(15, 23, 42, 0.94) 0%, rgba(30, 41, 59, 0.88) 100%);
    }

    .dark-section-mask {
      background: linear-gradient(180deg, #0F172A 0%, #1E293B 100%);
    }

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

    .gradient-text {
      background: linear-gradient(90deg, #0284C7, #38BDF8);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .stat-badge {
      box-shadow: 0 4px 20px rgba(2, 132, 199, 0.15);
    }