/* roulang page: index */
:root {
      --brand-dark: #0f172a;
      --brand-surface: #1e293b;
      --brand-cyan: #0ea5e9;
      --brand-accent: #06b6d4;
      --brand-orange: #f97316;
      --text-main: #0f172a;
      --text-muted: #64748b;
      --bg-light: #f8fafc;
      --bg-dark: #0b0f17;
    }
    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
    }
    .hero-mask {
      background: linear-gradient(135deg, rgba(11, 15, 23, 0.92) 0%, rgba(15, 23, 42, 0.85) 60%, rgba(14, 165, 233, 0.25) 100%);
    }
    .custom-shadow {
      box-shadow: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
    }
    .custom-shadow:hover {
      box-shadow: 0 12px 28px -4px rgba(14, 165, 233, 0.15);
    }
    .dark-card-glow {
      border: 1px solid rgba(255, 255, 255, 0.08);
      background: rgba(15, 23, 42, 0.6);
      backdrop-filter: blur(12px);
    }
    .dark-card-glow:hover {
      border-color: rgba(14, 165, 233, 0.4);
    }
    .tab-active {
      border-color: #0ea5e9;
      color: #0ea5e9;
      background-color: rgba(14, 165, 233, 0.08);
    }