/* roulang page: index */
:root {
            --primary: #0F4C5C;
            --primary-hover: #0b3945;
            --accent: #E36414;
            --accent-hover: #c7540d;
            --bg-light: #F8FAFC;
            --text-main: #0F172A;
            --text-body: #334155;
            --text-muted: #64748B;
            --border-line: #E2E8F0;
        }
        * { box-sizing: border-box; }
        html { scroll-behavior: smooth; }
        body {
            font-family: system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            color: var(--text-body);
            background-color: var(--bg-light);
            line-height: 1.8;
            overflow-x: hidden;
            margin: 0;
            padding: 0;
        }
        h1, h2, h3, h4 { color: var(--text-main); letter-spacing: -0.015em; font-weight: 700; }
        p { margin-bottom: 1.25rem; }
        .hero-banner {
            background-image: linear-gradient(rgba(10, 37, 44, 0.88), rgba(10, 37, 44, 0.94)), url('/assets/images/094e7fcedfa02b8e.webp');
            background-size: cover;
            background-position: center;
        }
        .deep-banner {
            background-image: linear-gradient(rgba(10, 37, 44, 0.95), rgba(10, 37, 44, 0.98)), url('/assets/images/54375e6bd75ee70a.webp');
            background-size: cover;
            background-position: center;
        }
        .card-custom {
            background: #FFFFFF;
            border: 1px solid var(--border-line);
            box-shadow: 0 4px 20px -2px rgba(15, 76, 92, 0.05);
            transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .card-custom:hover {
            transform: translateY(-4px);
            box-shadow: 0 12px 28px -4px rgba(15, 76, 92, 0.12);
            border-color: #CBD5E1;
        }
        .btn-accent {
            background-color: var(--accent);
            color: #FFFFFF;
            transition: all 0.25s ease;
        }
        .btn-accent:hover {
            background-color: var(--accent-hover);
            box-shadow: 0 4px 12px rgba(227, 100, 20, 0.3);
        }
        .btn-primary {
            background-color: var(--primary);
            color: #FFFFFF;
            transition: all 0.25s ease;
        }
        .btn-primary:hover {
            background-color: var(--primary-hover);
        }
        details > summary { list-style: none; cursor: pointer; }
        details > summary::-webkit-details-marker { display: none; }