/* roulang page: index */
:root {
      --primary: #1D4ED8;
      --primary-hover: #1E40AF;
      --accent: #0284C7;
      --accent-light: #E0F2FE;
      --bg-base: #F8FAFC;
      --bg-card: #FFFFFF;
      --bg-dark: #0F172A;
      --text-main: #0F172A;
      --text-muted: #475569;
      --border-subtle: #E2E8F0;
    }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-base);
      color: var(--text-main);
      overflow-x: hidden;
      margin: 0;
      padding: 0;
    }
    .custom-shadow {
      box-shadow: 0 10px 25px -5px rgba(15, 23, 42, 0.05), 0 8px 10px -6px rgba(15, 23, 42, 0.03);
    }
    .custom-shadow-lg {
      box-shadow: 0 20px 30px -10px rgba(15, 23, 42, 0.08), 0 10px 15px -3px rgba(15, 23, 42, 0.04);
    }
    .interactive-card {
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .interactive-card:hover {
      transform: translateY(-4px);
      box-shadow: 0 20px 35px -5px rgba(2, 132, 199, 0.12);
      border-color: #BAE6FD;
    }
    /* 手风琴平滑交互 */
    details summary::-webkit-details-marker {
      display: none;
    }
    details[open] summary .faq-icon {
      transform: rotate(180deg);
    }
    .hero-bg-overlay {
      background: linear-gradient(135deg, rgba(255, 255, 255, 0.94) 0%, rgba(240, 249, 255, 0.90) 100%);
    }