/* roulang page: index */
:root {
      --primary: #1E293B;
      --accent: #D97706;
      --text-main: #0F172A;
      --text-muted: #475569;
      --bg-light: #F8FAFC;
      --border-color: #E2E8F0;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      color: var(--text-main);
      background-color: #ffffff;
      font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
      line-height: 1.7;
    }
    .hero-slide {
      transition: opacity 0.8s ease-in-out;
    }
    .tab-content {
      display: none;
    }
    .tab-content.active {
      display: block;
    }