/* roulang page: index */
:root {
            --primary: #1D4ED8;
            --primary-dark: #1E40AF;
            --accent: #0D9488;
            --bg-light: #F8FAFC;
            --text-main: #0F172A;
            --text-muted: #475569;
            --border-color: #E2E8F0;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            background-color: var(--bg-light);
            color: var(--text-main);
            line-height: 1.6;
        }
        .hero-bg-overlay {
            background: linear-gradient(135deg, rgba(15, 23, 42, 0.92) 0%, rgba(30, 58, 138, 0.85) 100%);
        }
        .card-shadow {
            box-shadow: 0 4px 20px -2px rgba(15, 23, 42, 0.05), 0 2px 6px -1px rgba(15, 23, 42, 0.02);
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .card-shadow:hover {
            transform: translateY(-4px);
            box-shadow: 0 20px 25px -5px rgba(29, 78, 216, 0.08), 0 10px 10px -5px rgba(29, 78, 216, 0.04);
        }