/* roulang page: index */
:root {
            --bg-primary: #0B0F19;
            --bg-secondary: #111827;
            --bg-deep: #030712;
            --accent-blue: #0284C7;
            --accent-cyan: #06B6D4;
            --accent-green: #10B981;
            --text-heading: #F8FAFC;
            --text-body: #94A3B8;
            --text-muted: #64748B;
            --border-glass: rgba(255, 255, 255, 0.08);
            --border-glow: rgba(6, 182, 212, 0.4);
            --radius-default: 12px;
            --radius-large: 16px;
        }

        body {
            background-color: var(--bg-primary);
            color: var(--text-body);
            font-family: system-ui, -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            overflow-x: hidden;
            line-height: 1.7;
        }

        /* 玻璃拟态卡片 */
        .glass-panel {
            background: rgba(17, 24, 39, 0.78);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border: 1px solid var(--border-glass);
            border-radius: var(--radius-large);
            box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

        .glass-panel:hover {
            border-color: var(--border-glow);
            box-shadow: 0 14px 35px -8px rgba(6, 182, 212, 0.15);
            transform: translateY(-2px);
        }

        /* 发光按钮 */
        .glow-btn-primary {
            background: linear-gradient(135deg, #0284C7 0%, #06B6D4 100%);
            color: #ffffff;
            font-weight: 600;
            border-radius: var(--radius-default);
            padding: 0.85rem 1.75rem;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            transition: all 0.25s ease;
            box-shadow: 0 0 0 rgba(6, 182, 212, 0);
        }

        .glow-btn-primary:hover {
            box-shadow: 0 0 22px rgba(6, 182, 212, 0.6), 0 0 40px rgba(2, 132, 199, 0.25);
            transform: translateY(-2px);
        }

        .glow-btn-primary:active {
            transform: translateY(0);
        }

        .glow-btn-secondary {
            background: rgba(255, 255, 255, 0.05);
            color: #F8FAFC;
            font-weight: 500;
            border: 1px solid rgba(255, 255, 255, 0.15);
            border-radius: var(--radius-default);
            padding: 0.85rem 1.75rem;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            transition: all 0.25s ease;
        }

        .glow-btn-secondary:hover {
            background: rgba(255, 255, 255, 0.1);
            border-color: var(--accent-cyan);
            color: #ffffff;
            transform: translateY(-2px);
        }

        /* 标签与徽章 */
        .tech-badge {
            display: inline-flex;
            align-items: center;
            gap: 0.4rem;
            padding: 0.25rem 0.75rem;
            border-radius: 9999px;
            font-size: 0.8125rem;
            font-weight: 500;
            background: rgba(6, 182, 212, 0.1);
            color: #38BDF8;
            border: 1px solid rgba(6, 182, 212, 0.25);
        }

        /* 手风琴展开动画 */
        .faq-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease-out, opacity 0.3s ease;
            opacity: 0;
        }

        .faq-item.active .faq-content {
            max-height: 240px;
            opacity: 1;
        }

        .faq-item.active .faq-arrow {
            transform: rotate(180deg);
            color: #38BDF8;
        }

        /* 网格背景线 */
        .tech-grid-bg {
            background-size: 40px 40px;
            background-image: 
                linear-gradient(to right, rgba(255, 255, 255, 0.03) 1px, transparent 1px),
                linear-gradient(to bottom, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
        }