/* roulang page: index */
:root {
      --primary-deep: #0A1929;
      --accent-cyan: #00E5FF;
      --cta-orange: #FF6B35;
      --glass-bg: rgba(18, 30, 41, 0.75);
      --glass-border: rgba(255, 255, 255, 0.12);
      --text-primary: #F0F4F8;
      --text-secondary: #B0C4DE;
      --text-muted: #7A8B9E;
      --shadow-glow-orange: 0 0 18px rgba(255, 107, 53, 0.4);
      --shadow-glow-cyan: 0 0 14px rgba(0, 229, 255, 0.3);
      --radius-card: 20px;
      --radius-btn: 40px;
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
      background-color: var(--primary-deep);
      color: var(--text-primary);
      line-height: 1.65;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      box-shadow: 0 20px 35px rgba(0,0,0,0.5), 0 0 0 1px rgba(0,229,255,0.08);
    }
    .glass-nav {
      background: rgba(8, 22, 36, 0.8);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .btn-primary {
      background: var(--cta-orange);
      color: white;
      font-weight: 600;
      padding: 0.9rem 2.2rem;
      border-radius: var(--radius-btn);
      border: none;
      box-shadow: 0 8px 18px rgba(255, 107, 53, 0.35);
      transition: all 0.3s ease;
      letter-spacing: 0.5px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
    }
    .btn-primary:hover {
      background: #ff7f50;
      box-shadow: 0 12px 24px rgba(255, 107, 53, 0.55);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--accent-cyan);
      color: var(--accent-cyan);
      font-weight: 600;
      padding: 0.9rem 2.2rem;
      border-radius: var(--radius-btn);
      backdrop-filter: blur(8px);
      transition: all 0.3s ease;
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
    }
    .btn-outline:hover {
      background: rgba(0, 229, 255, 0.12);
      box-shadow: var(--shadow-glow-cyan);
      transform: translateY(-2px);
    }
    .hover-lift {
      transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s;
    }
    .hover-lift:hover {
      transform: translateY(-8px);
      box-shadow: 0 28px 40px rgba(0,0,0,0.7), 0 0 20px rgba(0,229,255,0.2);
      border-color: rgba(0,229,255,0.3);
    }
    .underline-cyan {
      position: relative;
    }
    .underline-cyan::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2.5px;
      background: var(--accent-cyan);
      transition: width 0.3s ease;
      border-radius: 2px;
    }
    .underline-cyan:hover::after {
      width: 100%;
    }
    .text-glow-cyan {
      color: var(--accent-cyan);
      text-shadow: 0 0 8px rgba(0,229,255,0.5);
    }
    .hero-bg {
      background: radial-gradient(circle at 30% 40%, rgba(0,229,255,0.08) 0%, transparent 50%),
                  linear-gradient(135deg, #0A1929 0%, #0B1E33 100%);
      position: relative;
      overflow: hidden;
    }
    .fluid-effect {
      position: absolute;
      width: 600px;
      height: 600px;
      background: radial-gradient(circle, rgba(0,229,255,0.15) 0%, transparent 70%);
      filter: blur(70px);
      border-radius: 50%;
      animation: floatFluid 12s infinite alternate ease-in-out;
    }
    @keyframes floatFluid {
      0% { transform: translate(0%, 0%) scale(1); }
      100% { transform: translate(15%, -10%) scale(1.2); }
    }
    .number-counter {
      font-variant-numeric: tabular-nums;
      font-weight: 700;
    }
    .faq-accordion {
      border-bottom: 1px solid rgba(255,255,255,0.1);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.45s ease-in-out, padding 0.3s;
    }
    .faq-item.active .faq-answer {
      max-height: 300px;
      padding-bottom: 1.2rem;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
      color: var(--cta-orange);
    }
    @media (max-width: 768px) {
      .glass-card {
        backdrop-filter: blur(10px);
      }
      .hero-title {
        font-size: 2.5rem !important;
        line-height: 1.3;
      }
    }