/* roulang page: index */
:root {
            --brand-blue: #0052D9;
            --brand-green: #00C58E;
            --brand-dark: #0B132B;
            --brand-slate: #1E293B;
            --brand-muted: #64748B;
            --brand-light: #F8FAFC;
            --brand-subtle: #EEF2F6;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            color: var(--brand-slate);
            background-color: #FFFFFF;
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            line-height: 1.75;
        }
        .hero-pattern {
            background-image: linear-gradient(135deg, rgba(11, 19, 43, 0.94) 0%, rgba(0, 82, 217, 0.88) 100%), url('/assets/images/31bd46006350e221.jpg');
            background-size: cover;
            background-position: center;
        }
        .tab-btn.active {
            background-color: var(--brand-blue);
            color: #ffffff;
        }