/* roulang page: index */
:root {
            --primary: #1B49D6;
            --primary-hover: #1338A8;
            --accent: #00B894;
            --bg-light: #F8FAFC;
            --bg-white: #FFFFFF;
            --dark-surface: #0F172A;
            --text-heading: #0F172A;
            --text-body: #334155;
            --text-muted: #64748B;
            --border-color: #E2E8F0;
            --radius-lg: 16px;
            --radius-sm: 8px;
            --shadow-card: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
            --shadow-hover: 0 20px 25px -5px rgba(15, 23, 42, 0.1), 0 8px 10px -6px rgba(15, 23, 42, 0.04);
            --transition-smooth: all 0.28s ease-in-out;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            background-color: var(--bg-light);
            color: var(--text-body);
            line-height: 1.65;
            margin: 0;
            padding: 0;
            overflow-x: hidden;
        }

        h1, h2, h3, h4, h5, h6 {
            color: var(--text-heading);
            font-weight: 700;
            line-height: 1.35;
        }

        a {
            text-decoration: none;
            transition: var(--transition-smooth);
        }

        .section-padding {
            padding-top: 5rem;
            padding-bottom: 5rem;
        }
        @media (min-width: 992px) {
            .section-padding {
                padding-top: 6.5rem;
                padding-bottom: 6.5rem;
            }
        }

        /* 顶部导航 */
        .site-header {
            background: rgba(255, 255, 255, 0.88);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border-color);
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            z-index: 1030;
            transition: var(--transition-smooth);
        }
        .navbar-brand-text {
            font-size: 1.35rem;
            font-weight: 800;
            letter-spacing: -0.5px;
            color: var(--text-heading);
        }
        .navbar-brand-text span {
            color: var(--primary);
        }

        /* 统一自定义按钮 */
        .btn-custom-primary {
            background-color: var(--primary);
            color: #ffffff;
            border-radius: var(--radius-sm);
            padding: 0.75rem 1.75rem;
            font-weight: 600;
            border: 1px solid transparent;
            min-height: 44px;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            transition: var(--transition-smooth);
        }
        .btn-custom-primary:hover {
            background-color: var(--primary-hover);
            color: #ffffff;
            transform: translateY(-2px);
            box-shadow: 0 8px 16px rgba(27, 73, 214, 0.25);
        }
        .btn-custom-secondary {
            background-color: #ffffff;
            color: var(--text-heading);
            border-radius: var(--radius-sm);
            padding: 0.75rem 1.75rem;
            font-weight: 600;
            border: 1px solid var(--border-color);
            min-height: 44px;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            transition: var(--transition-smooth);
        }
        .btn-custom-secondary:hover {
            background-color: #F1F5F9;
            color: var(--primary);
            border-color: #CBD5E1;
        }

        /* 卡片基础系统 */
        .system-card {
            background: var(--bg-white);
            border-radius: var(--radius-lg);
            border: 1px solid var(--border-color);
            box-shadow: var(--shadow-card);
            transition: var(--transition-smooth);
            height: 100%;
        }
        .system-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-hover);
            border-color: #CBD5E1;
        }

        /* Hero 区块微调 */
        .hero-banner {
            position: relative;
            padding-top: 8.5rem;
            padding-bottom: 5.5rem;
            background: linear-gradient(180deg, #F0F4FF 0%, #F8FAFC 100%);
            border-bottom: 1px solid var(--border-color);
        }
        .hero-preview-box {
            background: #ffffff;
            border-radius: var(--radius-lg);
            border: 1px solid var(--border-color);
            box-shadow: 0 25px 50px -12px rgba(15, 23, 42, 0.12);
            overflow: hidden;
        }

        /* 数据指标横条 */
        .metric-badge-box {
            background: #ffffff;
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            box-shadow: var(--shadow-card);
            padding: 2.25rem 1.5rem;
        }

        /* 深色视效演示舱 */
        .geek-console-section {
            background-color: var(--dark-surface);
            color: #F8FAFC;
        }
        .geek-console-section h2, .geek-console-section h3 {
            color: #ffffff;
        }
        .code-window-mockup {
            background: #090D16;
            border: 1px solid #1E293B;
            border-radius: 12px;
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
            font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
        }

        /* 徽章与标签 */
        .tag-pill {
            display: inline-block;
            padding: 0.35rem 0.85rem;
            font-size: 0.85rem;
            font-weight: 600;
            color: var(--primary);
            background-color: #EBF0FF;
            border-radius: 50px;
        }
        .tag-pill-accent {
            color: #047857;
            background-color: #D1FAE5;
        }

        /* 手风琴折叠面板重置 */
        .accordion-item {
            border: 1px solid var(--border-color);
            border-radius: var(--radius-sm) !important;
            margin-bottom: 1rem;
            overflow: hidden;
            background: #ffffff;
        }
        .accordion-button {
            font-weight: 600;
            color: var(--text-heading);
            padding: 1.25rem 1.5rem;
        }
        .accordion-button:not(.collapsed) {
            color: var(--primary);
            background-color: #F8FAFC;
            box-shadow: none;
        }
        .accordion-button:focus {
            box-shadow: none;
            border-color: var(--border-color);
        }

        /* 页脚 */
        .site-footer {
            background-color: #0B1120;
            color: #94A3B8;
            border-top: 1px solid #1E293B;
            padding-top: 4.5rem;
            padding-bottom: 3.5rem;
        }
        .site-footer a {
            color: #94A3B8;
        }
        .site-footer a:hover {
            color: #ffffff;
        }

        /* 移动端保障与折行 */
        @media (max-width: 767.98px) {
            .navbar-brand-text {
                font-size: 1.15rem;
            }
            .hero-banner {
                padding-top: 7rem;
                padding-bottom: 3.5rem;
            }
        }