/* roulang page: index */
:root {
            --bg-deep: #060B18;
            --bg-card: rgba(15, 23, 42, 0.72);
            --brand-blue: #0066FF;
            --brand-glow: #00E5FF;
            --accent-orange: #FF6B00;
            --border-glass: rgba(255, 255, 255, 0.12);
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            background-color: var(--bg-deep);
            color: #F8FAFC;
            font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "WenQuanYi Micro Hei", sans-serif;
            overflow-x: hidden;
        }
        .glass-panel {
            background: var(--bg-card);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border: 1px solid var(--border-glass);
            box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.5), inset 0 1px 0 rgba(255, 255, 255, 0.1);
        }
        .glass-panel-glow {
            background: linear-gradient(135deg, rgba(15, 23, 42, 0.85), rgba(6, 11, 24, 0.95));
            border: 1px solid rgba(0, 229, 255, 0.25);
            backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px);
        }
        .btn-glow {
            background: linear-gradient(135deg, #0066FF 0%, #00D2FF 100%);
            box-shadow: 0 0 20px rgba(0, 102, 255, 0.45);
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .btn-glow:hover {
            box-shadow: 0 0 30px rgba(0, 229, 255, 0.7);
            transform: translateY(-2px);
        }
        .hero-bg {
            background: linear-gradient(180deg, rgba(6, 11, 24, 0.82) 0%, rgba(6, 11, 24, 0.95) 100%), url('/assets/images/39ef7473b2f97b6f.jpg') center/cover no-repeat;
        }
        .section-separator {
            background: radial-gradient(circle at 50% 50%, rgba(0, 102, 255, 0.15) 0%, transparent 70%);
        }
        .faq-item-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease-out;
        }
        .faq-item.active .faq-item-content {
            max-height: 240px;
        }
        .faq-item.active .faq-icon {
            transform: rotate(180deg);
        }