/* roulang page: index */
:root {
      --bg-deep: #0a0f1d;
      --bg-darker: #0d1527;
      --primary-blue: #2563eb;
      --neon-cyan: #06b6d4;
      --neon-blue: #3b82f6;
      --glass-bg: rgba(16, 26, 48, 0.72);
      --glass-border: rgba(80, 140, 255, 0.18);
      --glass-hover-border: rgba(6, 182, 212, 0.45);
      --text-main: #f8fafc;
      --text-muted: #94a3b8;
    }
    
    body {
      background-color: var(--bg-deep);
      color: var(--text-main);
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      line-height: 1.75;
      overflow-x: hidden;
    }

    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--glass-border);
      box-shadow: 0 12px 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: var(--glass-hover-border);
      transform: translateY(-4px);
      box-shadow: 0 16px 40px 0 rgba(37, 99, 235, 0.25);
    }

    .neon-btn-primary {
      background: linear-gradient(135deg, #2563eb, #06b6d4);
      box-shadow: 0 0 22px rgba(59, 130, 246, 0.55);
      transition: all 0.3s ease;
    }

    .neon-btn-primary:hover {
      box-shadow: 0 0 32px rgba(6, 182, 212, 0.85);
      transform: translateY(-2px);
    }

    .neon-btn-outline {
      border: 1px solid var(--neon-blue);
      box-shadow: inset 0 0 12px rgba(59, 130, 246, 0.2);
      transition: all 0.3s ease;
    }

    .neon-btn-outline:hover {
      background: rgba(59, 130, 246, 0.15);
      border-color: var(--neon-cyan);
      box-shadow: 0 0 20px rgba(6, 182, 212, 0.4);
    }

    .text-glow {
      text-shadow: 0 0 16px rgba(59, 130, 246, 0.6);
    }

    .bg-mesh-radial {
      background-image: radial-gradient(circle at 50% 0%, rgba(37, 99, 235, 0.18) 0%, transparent 65%),
                        radial-gradient(circle at 85% 30%, rgba(6, 182, 212, 0.12) 0%, transparent 50%);
    }

    /* 移动端汉堡抽屉过渡 */
    #mobile-menu {
      transition: max-height 0.35s ease-in-out, opacity 0.3s ease-in-out;
    }