/* roulang page: index */
:root {
      --neon-blue: #00E5FF;
      --neon-purple: #B44CFF;
      --deep-space: #0A0E17;
      --graphite: #141B26;
      --text-primary: #f1f5f9;
      --text-secondary: #94a3b8;
      --border-glow: rgba(0,229,255,0.15);
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      background-color: var(--deep-space);
      color: var(--text-primary);
      line-height: 1.7;
      margin: 0;
      -webkit-font-smoothing: antialiased;
    }
    .glass-card {
      background: rgba(20, 27, 38, 0.6);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--border-glow);
      border-radius: 16px;
      box-shadow: 0 8px 32px rgba(0,0,0,0.4), 0 0 0 1px rgba(0,229,255,0.08);
      transition: all 300ms ease;
    }
    .glass-card:hover {
      border-color: rgba(0,229,255,0.4);
      transform: translateY(-4px);
    }
    .text-glow-blue {
      background: linear-gradient(to right, var(--neon-blue), var(--neon-purple));
      -webkit-background-clip: text;
      background-clip: text;
      color: transparent;
    }
    .hud-border {
      border: 1px solid rgba(0,229,255,0.25);
      box-shadow: 0 0 15px rgba(0,229,255,0.1);
    }
    .neon-divider {
      height: 2px;
      background: linear-gradient(90deg, var(--neon-blue), var(--neon-purple), transparent);
    }
    .btn-primary {
      background-color: var(--neon-blue);
      color: #0A0E17;
      font-weight: 700;
      border-radius: 9999px;
      padding: 0.75rem 2rem;
      box-shadow: 0 0 20px rgba(0,229,255,0.5), 0 0 60px rgba(180,76,255,0.3);
      transition: all 300ms ease;
      display: inline-block;
      text-align: center;
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      box-shadow: 0 0 35px rgba(0,229,255,0.8), 0 0 80px rgba(180,76,255,0.4);
      transform: scale(1.05);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--neon-blue);
      color: var(--neon-blue);
      font-weight: 600;
      border-radius: 9999px;
      padding: 0.75rem 2rem;
      transition: all 300ms ease;
      display: inline-block;
      text-align: center;
      cursor: pointer;
    }
    .btn-outline:hover {
      background: rgba(0,229,255,0.1);
      border-color: #fff;
      color: #fff;
    }
    .kpi-number {
      font-family: 'DIN Alternate', 'SF Mono', monospace;
      font-weight: 700;
    }
    .hero-bg {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
    }
    .hero-bg::after {
      content: '';
      position: absolute;
      inset: 0;
      background: radial-gradient(circle at 30% 40%, rgba(0,229,255,0.15), transparent 70%),
                  radial-gradient(circle at 70% 60%, rgba(180,76,255,0.1), transparent 70%);
      backdrop-filter: blur(2px);
      -webkit-backdrop-filter: blur(2px);
    }
    .speed-blur {
      filter: blur(2px);
      opacity: 0.7;
    }
    .hamburger-line {
      display: block;
      width: 24px;
      height: 2px;
      background: #fff;
      margin: 5px 0;
      transition: all 0.3s;
      box-shadow: 0 0 8px rgba(0,229,255,0.7);
    }
    .mobile-menu-open .hamburger-line:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
    .mobile-menu-open .hamburger-line:nth-child(2) { opacity: 0; }
    .mobile-menu-open .hamburger-line:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }
    details summary::-webkit-details-marker { display: none; }
    details summary { list-style: none; }
    @media (max-width: 768px) {
      .hero-bg { background-image: url('/assets/images/backpic/back-2.webp'); }
    }