/* roulang page: index */
:root {
            --bg-main: #0A0F1D;
            --bg-secondary: #0F172A;
            --primary: #2563EB;
            --accent-cyan: #06B6D4;
            --accent-green: #10B981;
            --text-main: #F8FAFC;
            --text-muted: #94A3B8;
            --text-sub: #64748B;
            --card-glass: rgba(30, 41, 59, 0.65);
            --border-glass: rgba(255, 255, 255, 0.08);
            --glow-shadow: 0 0 20px rgba(37, 99, 235, 0.35);
        }

        html {
            scroll-behavior: smooth;
            background-color: var(--bg-main);
            color: var(--text-main);
            font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
        }

        body {
            overflow-x: hidden;
            line-height: 1.75;
        }

        /* 玻璃拟态卡片 */
        .glass-panel {
            background: var(--card-glass);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border: 1px solid var(--border-glass);
            box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.12), 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: rgba(6, 182, 212, 0.4);
            box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 15px 35px -5px rgba(6, 182, 212, 0.2);
            transform: translateY(-3px);
        }

        /* 发光按钮 */
        .btn-glow-primary {
            background: linear-gradient(135deg, #2563EB 0%, #1D4ED8 100%);
            box-shadow: 0 0 18px rgba(37, 99, 235, 0.45);
            transition: all 0.25s ease;
        }

        .btn-glow-primary:hover {
            background: linear-gradient(135deg, #3B82F6 0%, #2563EB 100%);
            box-shadow: 0 0 25px rgba(6, 182, 212, 0.7);
            transform: translateY(-2px);
        }

        .btn-glow-secondary {
            background: rgba(15, 23, 42, 0.8);
            border: 1px solid rgba(6, 182, 212, 0.5);
            box-shadow: 0 0 12px rgba(6, 182, 212, 0.2);
            transition: all 0.25s ease;
        }

        .btn-glow-secondary:hover {
            background: rgba(30, 41, 59, 0.9);
            border-color: #06B6D4;
            box-shadow: 0 0 20px rgba(6, 182, 212, 0.45);
            transform: translateY(-2px);
        }

        /* 终端代码示意卡片 */
        .code-window {
            background: #060B14;
            border: 1px solid rgba(255, 255, 255, 0.1);
            font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
        }

        /* FAQ 手风琴动画 */
        .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-icon {
            transform: rotate(180deg);
            color: var(--accent-cyan);
        }

        /* 自定义滚动条 */
        ::-webkit-scrollbar {
            width: 8px;
            height: 8px;
        }
        ::-webkit-scrollbar-track {
            background: #0A0F1D;
        }
        ::-webkit-scrollbar-thumb {
            background: #1E293B;
            border-radius: 4px;
        }
        ::-webkit-scrollbar-thumb:hover {
            background: #2563EB;
        }