/* roulang page: index */
:root {
            --primary: #0F766E;
            --secondary: #0284C7;
            --surface-bg: #F8FAFC;
            --text-main: #0F172A;
            --text-muted: #475569;
            --border-line: #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(--surface-bg); color: var(--text-main); }
        .hero-gradient-overlay { background: linear-gradient(135deg, rgba(15, 23, 42, 0.94) 0%, rgba(15, 118, 110, 0.85) 100%); }
        .card-elevated { transition: transform 0.25s ease, box-shadow 0.25s ease; }
        .card-elevated:hover { transform: translateY(-4px); box-shadow: 0 12px 24px -10px rgba(15, 118, 110, 0.15); }