/* roulang page: index */
:root {
            --color-primary: #0D9488;
            --color-primary-dark: #0f766e;
            --color-accent: #6366F1;
            --color-slate-900: #0F172A;
            --color-slate-800: #1E293B;
            --color-slate-100: #F1F5F9;
            --color-paper: #F8FAFC;
            --font-stack: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
        }
        body {
            font-family: var(--font-stack);
            background-color: #FFFFFF;
            color: #334155;
            line-height: 1.75;
            -webkit-font-smoothing: antialiased;
        }
        h1, h2, h3, h4, h5, h6 {
            color: var(--color-slate-900);
            line-height: 1.3;
            letter-spacing: -0.02em;
        }
        .section-py {
            padding-top: 5rem;
            padding-bottom: 5rem;
        }
        @media (max-width: 768px) {
            .section-py {
                padding-top: 3rem;
                padding-bottom: 3rem;
            }
        }
        .card-custom {
            background: #FFFFFF;
            border-radius: 1rem;
            border: 1px solid rgba(226, 232, 240, 0.85);
            box-shadow: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
            transition: all 0.25s ease;
        }
        .card-custom:hover {
            transform: translateY(-4px);
            border-color: var(--color-primary);
            box-shadow: 0 12px 30px -4px rgba(13, 148, 136, 0.12);
        }
        .badge-cyan {
            background-color: #ECFDF5;
            color: #047857;
            border: 1px solid #A7F3D0;
        }
        .badge-indigo {
            background-color: #EEF2FF;
            color: #4338CA;
            border: 1px solid #C7D2FE;
        }
        .hero-gradient-text {
            background: linear-gradient(135deg, #0F172A 20%, #0D9488 65%, #6366F1 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .tab-btn.active {
            background-color: var(--color-primary);
            color: #ffffff;
            box-shadow: 0 4px 12px rgba(13, 148, 136, 0.25);
        }