/* roulang page: index */
:root {
            --primary-color: #ea580c;
            --primary-hover: #c2410c;
            --dark-surface: #0f172a;
            --light-bg: #f8fafc;
        }
        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            color: #1e293b;
            background-color: #ffffff;
            scroll-behavior: smooth;
        }
        .hero-pattern {
            background-color: #0b1120;
            background-image: radial-gradient(#ea580c 0.75px, transparent 0.75px), radial-gradient(#334155 0.75px, #0b1120 0.75px);
            background-size: 30px 30px;
            background-position: 0 0, 15px 15px;
        }
        .nav-link {
            position: relative;
            transition: color 0.2s ease;
        }
        .nav-link::after {
            content: '';
            position: absolute;
            width: 0;
            height: 2px;
            bottom: -4px;
            left: 50%;
            background-color: #ea580c;
            transition: all 0.25s ease;
            transform: translateX(-50%);
        }
        .nav-link:hover::after {
            width: 100%;
        }
        details > summary {
            list-style: none;
        }
        details > summary::-webkit-details-marker {
            display: none;
        }