/* roulang page: index */
:root {
            --bg-color: #090A0F;
            --card-color: #12131A;
            --accent-color: #00FFB2;
            --border-color: #232530;
            --text-color: #F4F5F7;
            --muted-color: #8A8F9E;
        }
        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
            scroll-behavior: smooth;
        }
        body {
            background-color: var(--bg-color);
            color: var(--text-color);
            font-family: Inter, system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            overflow-x: hidden;
            line-height: 1.6;
        }
        .glow-accent {
            text-shadow: 0 0 20px rgba(0, 255, 178, 0.45);
        }
        .btn-neon {
            background-color: var(--accent-color);
            color: #050608;
            font-weight: 700;
            transition: all 0.25s ease-in-out;
        }
        .btn-neon:hover {
            box-shadow: 0 0 25px rgba(0, 255, 178, 0.6);
            transform: translateY(-2px);
        }
        .glass-panel {
            background: rgba(18, 19, 26, 0.85);
            backdrop-filter: blur(12px);
            border: 1px solid var(--border-color);
        }
        .custom-card {
            background-color: var(--card-color);
            border: 1px solid var(--border-color);
            transition: border-color 0.3s ease, transform 0.3s ease;
        }
        .custom-card:hover {
            border-color: rgba(0, 255, 178, 0.5);
            transform: translateY(-4px);
        }
        .faq-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease-out;
        }
        .faq-item.active .faq-content {
            max-height: 400px;
        }
        .faq-item.active .faq-icon {
            transform: rotate(180deg);
        }