/* roulang page: index */
:root {
            --bs-primary: #1A2B4C;
            --bs-primary-rgb: 26, 43, 76;
            --bs-secondary: #C0392B;
            --bs-secondary-rgb: 192, 57, 43;
            --bs-body-bg: #FAFBFD;
            --bs-body-color: #4A5568;
            --bs-border-radius: 12px;
            --bs-border-radius-sm: 8px;
            --bs-border-radius-lg: 16px;
            --bs-card-shadow: 0 2px 8px rgba(26,43,76,0.04), 0 1px 3px rgba(0,0,0,0.02);
            --bs-card-shadow-hover: 0 8px 24px rgba(26,43,76,0.08), 0 2px 6px rgba(0,0,0,0.04);
            --bs-font-sans-serif: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', system-ui, sans-serif;
            --bs-font-monospace: 'Inter', 'SF Pro Display', system-ui, sans-serif;
            --color-deep-navy: #1A2B4C;
            --color-ai-red: #C0392B;
            --color-bg-light: #FAFBFD;
            --color-card-white: #FFFFFF;
            --color-section-alt: #F0F2F6;
            --color-text-body: #4A5568;
            --color-text-muted: #718096;
            --color-border-light: #E2E8F0;
            --nav-height-desktop: 130px;
            --nav-height-scrolled: 70px;
            --transition-smooth: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
        }

        *,
        *::before,
        *::after {
            box-sizing: border-box;
        }

        body {
            font-family: var(--bs-font-sans-serif);
            background-color: var(--bs-body-bg);
            color: var(--bs-body-color);
            line-height: 1.6;
            font-size: 16px;
            -webkit-font-smoothing: antialiased;
            padding-top: var(--nav-height-desktop);
            overflow-x: hidden;
        }

        h1, h2, h3, h4, h5, h6 {
            color: var(--color-deep-navy);
            font-weight: 600;
            margin-bottom: 0.75rem;
        }
        h1 { font-size: 48px; line-height: 60px; letter-spacing: -0.5px; font-weight: 700; }
        h2 { font-size: 36px; line-height: 44px; }
        h3 { font-size: 22px; line-height: 30px; }
        h4 { font-size: 18px; line-height: 26px; }
        p { margin-bottom: 1rem; color: var(--color-text-body); }
        a { color: var(--color-deep-navy); text-decoration: none; transition: color var(--transition-smooth); }
        a:hover { color: var(--color-ai-red); }
        img { max-width: 100%; height: auto; display: block; }

        .container {
            max-width: 1200px;
            padding-left: 24px;
            padding-right: 24px;
        }

        /* 自定义按钮系统 */
        .btn-primary-custom {
            background-color: var(--color-ai-red);
            border: 2px solid var(--color-ai-red);
            color: #FFFFFF;
            border-radius: var(--bs-border-radius-sm);
            padding: 14px 32px;
            font-weight: 600;
            font-size: 16px;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            transition: all var(--transition-smooth);
            white-space: nowrap;
            box-shadow: 0 4px 12px rgba(192,57,43,0.3);
        }
        .btn-primary-custom:hover {
            background-color: #A93226;
            border-color: #A93226;
            color: #FFFFFF;
            box-shadow: 0 6px 18px rgba(192,57,43,0.4);
            transform: translateY(-1px);
        }
        .btn-outline-custom {
            background: transparent;
            border: 2px solid var(--color-deep-navy);
            color: var(--color-deep-navy);
            border-radius: var(--bs-border-radius-sm);
            padding: 14px 32px;
            font-weight: 600;
            font-size: 16px;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            transition: all var(--transition-smooth);
        }
        .btn-outline-custom:hover {
            background-color: rgba(26,43,76,0.08);
            color: var(--color-deep-navy);
            border-color: var(--color-deep-navy);
            transform: translateY(-1px);
        }
        .btn-link-custom {
            color: var(--color-deep-navy);
            font-weight: 600;
            text-decoration: underline;
            text-underline-offset: 4px;
            transition: color var(--transition-smooth);
        }
        .btn-link-custom:hover { color: var(--color-ai-red); text-decoration: underline; }

        /* 卡片系统 */
        .custom-card {
            background: var(--color-card-white);
            border: 1px solid var(--color-border-light);
            border-radius: var(--bs-border-radius);
            box-shadow: var(--bs-card-shadow);
            padding: 32px;
            height: 100%;
            transition: all var(--transition-smooth);
        }
        .custom-card:hover {
            box-shadow: var(--bs-card-shadow-hover);
            transform: translateY(-4px);
            border-top: 3px solid var(--color-ai-red);
        }
        .custom-card .card-icon {
            font-size: 48px;
            color: var(--color-deep-navy);
            margin-bottom: 20px;
        }
        .custom-card h3 {
            color: var(--color-deep-navy);
            margin-bottom: 12px;
        }
        .tag-badge {
            display: inline-block;
            background: rgba(192,57,43,0.1);
            color: var(--color-ai-red);
            font-size: 13px;
            font-weight: 600;
            padding: 4px 12px;
            border-radius: 20px;
            margin-right: 6px;
            margin-bottom: 6px;
        }

        /* 导航 */
        .navbar-custom {
            background: rgba(255,255,255,0.98);
            backdrop-filter: blur(12px);
            box-shadow: 0 2px 12px rgba(0,0,0,0.04);
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            z-index: 1050;
            transition: all var(--transition-smooth);
            padding: 0;
        }
        .navbar-custom .top-brand-row {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 12px 0;
            border-bottom: 1px solid var(--color-border-light);
        }
        .brand-logo {
            font-size: 28px;
            font-weight: 700;
            color: var(--color-deep-navy);
            letter-spacing: 1px;
        }
        .brand-domain {
            font-size: 13px;
            color: var(--color-text-muted);
            margin-left: 4px;
        }
        .search-trigger {
            font-size: 20px;
            color: var(--color-deep-navy);
            cursor: pointer;
            transition: color 0.2s;
        }
        .search-trigger:hover { color: var(--color-ai-red); }
        .channel-nav {
            display: flex;
            align-items: center;
            gap: 24px;
            padding: 8px 0;
            overflow-x: auto;
            white-space: nowrap;
            -webkit-overflow-scrolling: touch;
        }
        .channel-nav a {
            color: var(--color-text-body);
            font-weight: 500;
            font-size: 15px;
            padding: 8px 4px;
            border-bottom: 2px solid transparent;
            transition: all 0.2s;
        }
        .channel-nav a.active, .channel-nav a:hover {
            color: var(--color-deep-navy);
            border-bottom-color: var(--color-ai-red);
        }
        .hot-tags {
            display: flex;
            gap: 12px;
            margin-left: 20px;
        }
        .hot-tag {
            font-size: 12px;
            background: #EDF2F7;
            color: var(--color-text-muted);
            padding: 4px 10px;
            border-radius: 20px;
            font-weight: 500;
        }
        .navbar-scrolled .top-brand-row { padding: 6px 0; border-bottom: none; }
        .navbar-scrolled .brand-logo { font-size: 22px; }
        .navbar-scrolled .channel-nav { padding: 4px 0; }
        .navbar-scrolled { box-shadow: 0 4px 20px rgba(0,0,0,0.08); }

        /* 移动端菜单 */
        .navbar-toggler-custom {
            border: none;
            font-size: 24px;
            color: var(--color-deep-navy);
            background: transparent;
            padding: 8px;
        }

        /* Hero */
        .hero-section {
            background: linear-gradient(135deg, #F4F7FC 0%, #FFFFFF 100%);
            padding: 80px 0;
        }
        .hero-img-wrapper {
            background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
            border-radius: 20px;
            min-height: 380px;
            position: relative;
            overflow: hidden;
        }
        .hero-img-wrapper::after {
            content: '';
            position: absolute;
            inset: 0;
            background: rgba(26,43,76,0.15);
            border-radius: 20px;
        }
        .stat-item {
            display: flex;
            align-items: baseline;
            gap: 6px;
            font-size: 24px;
            font-weight: 700;
            color: var(--color-deep-navy);
            font-family: var(--bs-font-monospace);
        }
        .stat-label {
            font-size: 14px;
            font-weight: 400;
            color: var(--color-text-muted);
        }

        /* 信任条 */
        .trust-bar {
            background: #FFFFFF;
            border-top: 1px solid var(--color-border-light);
            border-bottom: 1px solid var(--color-border-light);
        }
        .partner-logos img {
            filter: grayscale(1);
            opacity: 0.7;
            max-height: 36px;
            transition: 0.2s;
        }
        .partner-logos img:hover { filter: none; opacity: 1; }

        /* 产品/场景卡片 */
        .scene-card img {
            border-radius: 12px 12px 0 0;
            height: 220px;
            object-fit: cover;
            width: 100%;
        }
        .scene-card .card-body-area {
            padding: 24px;
        }

        /* 案例卡片 */
        .case-card {
            background: #FFFFFF;
            border-radius: 12px;
            overflow: hidden;
        }
        .case-metric {
            font-size: 32px;
            font-weight: 700;
            color: var(--color-deep-navy);
            font-family: var(--bs-font-monospace);
        }

        /* 数据计数器 */
        .counter-section {
            background: var(--color-section-alt);
        }
        .counter-value {
            font-size: 48px;
            font-weight: 700;
            color: var(--color-deep-navy);
            font-family: var(--bs-font-monospace);
        }

        /* 流程步骤 */
        .step-item {
            position: relative;
            text-align: center;
            padding: 20px;
        }
        .step-circle {
            width: 60px;
            height: 60px;
            background: var(--color-deep-navy);
            color: #fff;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 24px;
            margin: 0 auto 16px;
        }
        .step-connector {
            position: absolute;
            top: 50px;
            left: 70%;
            width: 40%;
            border-top: 2px dashed var(--color-border-light);
        }

        /* FAQ */
        .accordion-button:not(.collapsed) {
            background-color: #FFFFFF;
            color: var(--color-deep-navy);
            box-shadow: none;
            border-left: 4px solid var(--color-ai-red);
        }
        .accordion-button {
            font-weight: 600;
            font-size: 18px;
        }

        /* CTA */
        .cta-full {
            background: var(--color-deep-navy);
        }

        /* 页脚 */
        .footer-section {
            background: #FFFFFF;
            border-top: 1px solid var(--color-border-light);
        }

        @media (max-width: 992px) {
            body { padding-top: 120px; }
            h1 { font-size: 36px; line-height: 46px; }
            h2 { font-size: 28px; }
            .hero-section { padding: 40px 0; }
            .step-connector { display: none; }
            .faq-double-col .col-md-6 { width: 100%; }
        }
        @media (max-width: 768px) {
            .navbar-custom .top-brand-row { padding: 8px 0; }
            .channel-nav { gap: 12px; }
            .btn-primary-custom, .btn-outline-custom { width: 100%; }
        }
        @media (max-width: 576px) {
            .container { padding-left: 16px; padding-right: 16px; }
            h1 { font-size: 30px; line-height: 38px; }
            .custom-card { padding: 24px; }
        }