/* roulang page: index */
:root {
      --bg-dark: #070B14;
      --bg-surface: #0D1527;
      --brand-blue: #2563EB;
      --brand-cyan: #38BDF8;
      --brand-glow: #00F2FE;
      --text-main: #F8FAFC;
      --text-muted: #94A3B8;
      --border-glass: rgba(255, 255, 255, 0.08);
      --glass-card: rgba(15, 23, 42, 0.65);
    }
    body {
      background-color: var(--bg-dark);
      color: var(--text-main);
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      overflow-x: hidden;
      line-height: 1.7;
    }
    .glass-card {
      background: var(--glass-card);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--border-glass);
      box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .glass-card:hover {
      border-color: rgba(56, 189, 248, 0.35);
      transform: translateY(-3px);
      box-shadow: 0 14px 38px 0 rgba(2, 132, 199, 0.25);
    }
    .glow-btn-primary {
      background: linear-gradient(135deg, #0284C7 0%, #2563EB 100%);
      transition: all 0.25s ease;
      box-shadow: 0 0 16px rgba(37, 99, 235, 0.35);
    }
    .glow-btn-primary:hover {
      box-shadow: 0 0 24px rgba(56, 189, 248, 0.55);
      transform: translateY(-2px);
    }
    .text-glow {
      text-shadow: 0 0 18px rgba(56, 189, 248, 0.4);
    }
    .border-gradient {
      position: relative;
    }
    .border-gradient::before {
      content: "";
      position: absolute;
      inset: 0;
      border-radius: inherit;
      padding: 1px;
      background: linear-gradient(135deg, rgba(56, 189, 248, 0.4), rgba(37, 99, 235, 0.1), transparent);
      -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
      -webkit-mask-composite: xor;
      mask-composite: exclude;
      pointer-events: none;
    }
    .tab-content { display: none; }
    .tab-content.active { display: block; }