/* roulang page: index */
:root {
      --primary: #4F46E5;
      --primary-hover: #4338CA;
      --cyan: #06B6D4;
      --amber: #F59E0B;
      --bg-dark: #0F172A;
      --bg-card-dark: #1E293B;
      --text-main: #0F172A;
      --text-sub: #334155;
      --text-muted: #64748B;
      --border-color: #E2E8F0;
      --radius-xl: 1rem;
      --shadow-soft: 0 4px 20px -2px rgba(15, 23, 42, 0.05), 0 2px 6px -1px rgba(15, 23, 42, 0.03);
    }
    
    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      color: var(--text-main);
      background-color: #FAFAFC;
    }

    .glass-nav {
      background: rgba(255, 255, 255, 0.94);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
    }

    .card-shadow {
      box-shadow: var(--shadow-soft);
      transition: all 0.28s ease;
    }

    .card-shadow:hover {
      transform: translateY(-4px);
      box-shadow: 0 16px 30px -4px rgba(15, 23, 42, 0.08), 0 4px 10px -2px rgba(15, 23, 42, 0.04);
    }

    details > summary {
      list-style: none;
    }
    details > summary::-webkit-details-marker {
      display: none;
    }
    details[open] summary svg {
      transform: rotate(180deg);
    }