/* roulang page: index */
:root {
      --brand-primary: #1D4ED8;
      --brand-accent: #2563EB;
      --bg-base: #F8FAFC;
      --text-main: #0F172A;
      --text-muted: #334155;
      --text-sub: #64748B;
      --border-color: #E2E8F0;
    }
    body {
      font-family: system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-base);
      color: var(--text-main);
      overflow-x: hidden;
    }
    .custom-card {
      background: #FFFFFF;
      border: 1px solid #F1F5F9;
      box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.05);
      transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
    }
    .custom-card:hover {
      transform: translateY(-5px);
      box-shadow: 0 16px 32px -8px rgba(37, 99, 235, 0.12);
      border-color: #BFDBFE;
    }
    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
    }
    .accordion-content.open {
      max-height: 500px;
      transition: max-height 0.35s ease-in-out;
    }