/* roulang page: index */
:root {
      --primary-900: #0F172A;
      --primary-700: #1D4ED8;
      --primary-600: #2563EB;
      --accent-amber: #F59E0B;
      --accent-emerald: #10B981;
      --surface-bg: #F8FAFC;
      --surface-white: #FFFFFF;
      --text-main: #0F172A;
      --text-muted: #64748B;
      --border-color: #E2E8F0;
      --radius-sm: 6px;
      --radius-md: 10px;
      --radius-lg: 16px;
    }
    *, *::before, *::after {
      box-sizing: border-box;
    }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      color: var(--text-main);
      background-color: var(--surface-white);
      line-height: 1.65;
      -webkit-font-smoothing: antialiased;
    }
    .num-tabular {
      font-variant-numeric: tabular-nums;
    }
    .card-transition {
      transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    }
    .card-transition:hover {
      transform: translateY(-2px);
      box-shadow: 0 14px 28px -4px rgba(15, 23, 42, 0.08);
      border-color: #CBD5E1;
    }
    .hero-slide {
      display: none;
      opacity: 0;
      transition: opacity 0.6s ease-in-out;
    }
    .hero-slide.active {
      display: block;
      opacity: 1;
    }
    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .faq-item.expanded .faq-content {
      max-height: 240px;
    }
    .faq-item.expanded .faq-icon {
      transform: rotate(180deg);
    }