/* roulang page: index */
:root {
            --bg-deep: #070B19;
            --bg-card: rgba(15, 23, 42, 0.75);
            --border-glow: rgba(59, 130, 246, 0.25);
            --neon-blue: #3B82F6;
            --neon-cyan: #06B6D4;
        }
        body {
            background-color: var(--bg-deep);
            color: #CBD5E1;
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            overflow-x: hidden;
        }
        .glass-card {
            background: var(--bg-card);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border: 1px solid rgba(255, 255, 255, 0.08);
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .glass-card:hover {
            border-color: rgba(59, 130, 246, 0.5);
            transform: translateY(-4px);
            box-shadow: 0 16px 36px -10px rgba(37, 99, 235, 0.3);
        }
        .glow-btn-primary {
            background: linear-gradient(135deg, #1D4ED8 0%, #2563EB 50%, #06B6D4 100%);
            box-shadow: 0 0 20px rgba(37, 99, 235, 0.4);
            transition: all 0.3s ease;
        }
        .glow-btn-primary:hover {
            box-shadow: 0 0 30px rgba(6, 182, 212, 0.6);
            transform: translateY(-2px);
        }
        .glow-badge {
            background: rgba(6, 182, 212, 0.12);
            border: 1px solid rgba(6, 182, 212, 0.35);
        }
        .code-syntax {
            font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
        }
        .faq-body {
            transition: max-height 0.35s ease, opacity 0.3s ease;
            max-height: 0;
            overflow: hidden;
            opacity: 0;
        }
        .faq-body.open {
            max-height: 400px;
            opacity: 1;
        }