/* roulang page: index */
:root {
            --primary: #0F172A;
            --secondary: #0284C7;
            --accent: #10B981;
            --text-main: #334155;
            --border-light: #E2E8F0;
        }
        html { scroll-behavior: smooth; font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif; }
        .hero-overlay { background: linear-gradient(135deg, rgba(15, 23, 42, 0.94) 0%, rgba(11, 15, 25, 0.85) 100%); }
        .feature-card { transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1); }
        .feature-card:hover { transform: translateY(-4px); box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.08); }
        .tech-bg { background-color: #0B0F19; background-image: radial-gradient(rgba(2, 132, 199, 0.15) 1px, transparent 1px); background-size: 24px 24px; }
        .glass-panel { background: rgba(255, 255, 255, 0.85); backdrop-filter: blur(12px); border: 1px solid rgba(226, 232, 240, 0.8); }
        .glass-dark { background: rgba(19, 27, 46, 0.7); backdrop-filter: blur(12px); border: 1px solid rgba(255, 255, 255, 0.08); }