/* roulang page: index */
:root {
            --primary: #0066FF;
            --primary-dark: #0052CC;
            --accent: #10B981;
            --text-main: #334155;
            --text-muted: #64748B;
            --bg-light: #F8FAFC;
            --shadow-subtle: 0 4px 20px -2px rgba(15, 23, 42, 0.06);
            --shadow-hover: 0 12px 28px -4px rgba(0, 102, 255, 0.12);
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
            color: var(--text-main);
            background-color: var(--bg-light);
            line-height: 1.65;
        }
        .card-lift {
            transition: transform 0.25s ease, box-shadow 0.25s ease;
        }
        .card-lift:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-hover);
        }
        .hero-overlay {
            background: linear-gradient(135deg, rgba(15, 23, 42, 0.92) 0%, rgba(15, 23, 42, 0.78) 100%);
        }