/* roulang page: index */
:root {
      --primary: #2563EB;
      --primary-dark: #1D4ED8;
      --accent-green: #10B981;
      --text-main: #0F172A;
      --text-body: #334155;
      --text-muted: #64748B;
      --bg-light: #F8FAFC;
      --border-color: #E2E8F0;
      --card-shadow: 0 10px 25px -5px rgba(15, 23, 42, 0.04), 0 8px 10px -6px rgba(15, 23, 42, 0.04);
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
      color: var(--text-body);
      background-color: #FFFFFF;
      line-height: 1.7;
    }
    .card-hover {
      transition: transform 0.25s ease, box-shadow 0.25s ease;
      box-shadow: var(--card-shadow);
    }
    .card-hover:hover {
      transform: translateY(-4px);
      box-shadow: 0 20px 30px -10px rgba(15, 23, 42, 0.08), 0 12px 14px -8px rgba(15, 23, 42, 0.06);
    }
    .btn-action {
      transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .btn-action:hover {
      transform: translateY(-2px);
    }
    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease-out;
    }
    .accordion-item.active .accordion-content {
      max-height: 220px;
    }
    .accordion-item.active .accordion-icon {
      transform: rotate(180deg);
    }