/* roulang page: index */
:root {
            --primary: #0E4B5B;
            --secondary: #F4A261;
            --accent: #2EC4B6;
            --darkbg: #0A192F;
            --surface: #F8F9FA;
            --fontdark: #1D2A44;
            --border-soft: rgba(229, 231, 235, 0.8);
            --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.05);
        }
        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        body {
            font-family: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
            color: var(--fontdark);
            background-color: #FFFFFF;
            line-height: 1.75;
            -webkit-font-smoothing: antialiased;
        }
        .header-glass {
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            background-color: rgba(255, 255, 255, 0.92);
            border-bottom: 1px solid rgba(14, 75, 91, 0.08);
        }
        .custom-card {
            border: 1px solid var(--border-soft);
            box-shadow: var(--shadow-card);
            transition: transform 300ms cubic-bezier(0.4, 0, 0.2, 1), box-shadow 300ms cubic-bezier(0.4, 0, 0.2, 1);
        }
        .custom-card:hover {
            transform: translateY(-4px);
            box-shadow: 0 20px 35px -10px rgba(14, 75, 91, 0.12);
        }
        .hero-slide {
            transition: opacity 800ms ease-in-out, transform 800ms ease-in-out;
        }
        details summary::-webkit-details-marker {
            display: none;
        }
        details[open] .arrow-icon {
            transform: rotate(180deg);
        }
        .code-block {
            font-family: 'Menlo', 'Monaco', 'Courier New', monospace;
        }