/* roulang page: index */
:root {
      --deep-blue: #0A0E27;
      --champagne-gold: #D4AF37;
      --warm-amber: #C8963E;
      --soft-white: #F5F0E8;
      --card-bg: rgba(15, 25, 55, 0.7);
      --glass-border: rgba(212, 175, 55, 0.25);
      --glow-gold: 0 0 20px rgba(212, 175, 55, 0.15);
      --glow-strong: 0 0 30px rgba(212, 175, 55, 0.6);
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-sm: 8px;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      background-color: var(--deep-blue);
      color: var(--soft-white);
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
      line-height: 1.7;
      scroll-behavior: smooth;
      -webkit-font-smoothing: antialiased;
    }
    .serif {
      font-family: 'Noto Serif SC', '思源宋体', 'Times New Roman', serif;
    }
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-lg);
      box-shadow: var(--glow-gold);
    }
    .gold-text {
      color: var(--champagne-gold);
    }
    .gold-border {
      border-color: var(--champagne-gold);
    }
    .btn-primary {
      background: linear-gradient(135deg, #D4AF37 0%, #C8963E 100%);
      color: #0A0E27;
      font-weight: 700;
      border-radius: var(--radius-sm);
      padding: 0.75rem 2rem;
      transition: all 0.3s ease;
      box-shadow: 0 4px 12px rgba(212,175,55,0.4);
      border: none;
      cursor: pointer;
      display: inline-block;
      text-align: center;
      letter-spacing: 0.5px;
    }
    .btn-primary:hover {
      box-shadow: var(--glow-strong);
      transform: scale(1.03);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--champagne-gold);
      color: var(--champagne-gold);
      font-weight: 600;
      border-radius: var(--radius-sm);
      padding: 0.65rem 1.8rem;
      transition: all 0.3s ease;
      cursor: pointer;
      display: inline-block;
      text-align: center;
    }
    .btn-outline:hover {
      background: rgba(212,175,55,0.1);
      border-color: #fff;
      color: #fff;
    }
    .nav-blur {
      background: rgba(10, 14, 39, 0.8);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(212, 175, 55, 0.2);
    }
    .metric-grid-bg {
      background-image: linear-gradient(rgba(212,175,55,0.03) 1px, transparent 1px), linear-gradient(90deg, rgba(212,175,55,0.03) 1px, transparent 1px);
      background-size: 40px 40px;
    }
    .hero-backdrop {
      background: radial-gradient(circle at 30% 40%, rgba(212,175,55,0.08) 0%, transparent 70%);
    }
    .cta-glow {
      background: radial-gradient(circle at center, rgba(212,175,55,0.15) 0%, rgba(10,14,27,0.9) 70%);
    }
    input, textarea {
      background: rgba(20, 30, 60, 0.8);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-sm);
      padding: 0.8rem 1rem;
      color: var(--soft-white);
      transition: all 0.3s;
      width: 100%;
      outline: none;
      font-size: 1rem;
    }
    input:focus, textarea:focus {
      border-color: var(--champagne-gold);
      box-shadow: 0 0 15px rgba(212,175,55,0.4);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 1rem 0 0.5rem;
    }
    .comparison-bad {
      background: rgba(180, 60, 60, 0.15);
      border-left: 4px solid #b03a3a;
    }
    .comparison-good {
      background: rgba(15, 25, 55, 0.7);
      border-left: 4px solid var(--champagne-gold);
    }
    @media (max-width: 768px) {
      .mobile-menu {
        display: none;
        flex-direction: column;
        background: rgba(10, 14, 39, 0.95);
        backdrop-filter: blur(20px);
        position: absolute;
        top: 70px;
        left: 0;
        width: 100%;
        padding: 1.5rem;
        border-bottom: 1px solid var(--glass-border);
      }
      .mobile-menu.open {
        display: flex;
      }
    }