/* roulang page: index */
:root {
      --bg-base: #f8fafc;
      --card-bg: #ffffff;
      --brand-primary: #2563eb;
      --brand-accent: #10b981;
      --text-main: #0f172a;
      --text-muted: #64748b;
      --border-light: #e2e8f0;
      --border-dark: #334155;
      --radius-sm: 6px;
      --radius-md: 10px;
      --radius-lg: 14px;
      --shadow-soft: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
      --shadow-hover: 0 12px 30px -4px rgba(37, 99, 235, 0.12);
    }

    html {
      scroll-behavior: smooth;
      font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
      text-rendering: optimizeLegibility;
      -webkit-font-smoothing: antialiased;
    }

    body {
      background-color: var(--bg-base);
      color: var(--text-main);
      overflow-x: hidden;
      line-height: 1.7;
    }

    .glass-nav {
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
    }

    .custom-card {
      background: var(--card-bg);
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-soft);
      transition: transform 0.28s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.28s cubic-bezier(0.4, 0, 0.2, 1), border-color 0.28s ease;
    }

    .custom-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: #cbd5e1;
    }

    .btn-gradient {
      background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
      transition: all 0.25s ease;
      box-shadow: 0 4px 14px rgba(37, 99, 235, 0.28);
    }

    .btn-gradient:hover {
      background: linear-gradient(135deg, #1d4ed8 0%, #1e40af 100%);
      box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
      transform: translateY(-1px);
    }

    .coupon-ticket {
      background: linear-gradient(135deg, #ffffff 0%, #f1f5f9 100%);
      border: 1px dashed #cbd5e1;
      position: relative;
    }

    .coupon-ticket::before, .coupon-ticket::after {
      content: '';
      position: absolute;
      width: 18px;
      height: 18px;
      background: #0f172a;
      border-radius: 50%;
      top: 50%;
      transform: translateY(-50%);
    }
    .coupon-ticket::before { left: -10px; }
    .coupon-ticket::after { right: -10px; }

    .step-line::after {
      content: '';
      position: absolute;
      top: 2rem;
      left: 2rem;
      right: 2rem;
      height: 2px;
      background: #e2e8f0;
      z-index: 0;
    }
    @media (max-width: 1024px) {
      .step-line::after { display: none; }
    }