/* roulang page: index */
:root {
            --bg-base: #F8FAFC;
            --bg-surface: #FFFFFF;
            --bg-subtle: #F1F5F9;
            --bg-dark: #0B0F19;
            --bg-nav: #0F172A;
            --primary: #2563EB;
            --primary-dark: #1E40AF;
            --accent: #F59E0B;
            --accent-cyan: #06B6D4;
            --text-main: #0F172A;
            --text-muted: #334155;
            --text-light: #64748B;
            --border-color: #E2E8F0;
            --border-dark: #1E293B;
            --shadow-sm: 0 4px 6px -1px rgba(15, 23, 42, 0.04), 0 2px 4px -2px rgba(15, 23, 42, 0.02);
            --shadow-md: 0 10px 25px -5px rgba(15, 23, 42, 0.05), 0 8px 10px -6px rgba(15, 23, 42, 0.03);
            --shadow-hover: 0 20px 30px -10px rgba(37, 99, 235, 0.12), 0 10px 15px -5px rgba(15, 23, 42, 0.04);
            --radius-md: 12px;
            --radius-lg: 16px;
            --radius-full: 9999px;
            --container-max: 1240px;
        }

        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        html {
            scroll-behavior: smooth;
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            background-color: var(--bg-base);
            color: var(--text-main);
            line-height: 1.6;
        }

        body {
            overflow-x: hidden;
            background-color: var(--bg-base);
        }

        a {
            color: inherit;
            text-decoration: none;
            transition: all 0.25s ease-in-out;
        }

        img {
            max-width: 100%;
            height: auto;
            display: block;
        }

        .container {
            width: 100%;
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 24px;
        }

        /* 顶部两行导航 */
        .top-bar {
            background-color: var(--bg-dark);
            color: #94A3B8;
            font-size: 13px;
            border-bottom: 1px solid var(--border-dark);
            padding: 8px 0;
        }
        .top-bar-inner {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .top-bar-links span {
            margin-right: 20px;
        }

        .site-header {
            background-color: rgba(15, 23, 42, 0.95);
            backdrop-filter: blur(12px);
            position: sticky;
            top: 0;
            z-index: 1000;
            border-bottom: 1px solid rgba(255, 255, 255, 0.08);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 72px;
        }
        .logo {
            font-size: 20px;
            font-weight: 700;
            color: #FFFFFF;
            display: flex;
            align-items: center;
            gap: 8px;
            letter-spacing: -0.5px;
        }
        .logo-badge {
            background: linear-gradient(135deg, var(--primary), var(--accent-cyan));
            color: #fff;
            font-size: 11px;
            padding: 2px 6px;
            border-radius: 4px;
            font-weight: 600;
        }
        .main-nav {
            display: flex;
            align-items: center;
            gap: 28px;
        }
        .nav-link {
            color: #E2E8F0;
            font-size: 15px;
            font-weight: 500;
        }
        .nav-link:hover {
            color: #60A5FA;
        }
        .header-cta {
            display: flex;
            align-items: center;
            gap: 16px;
        }

        /* 按钮与徽章 */
        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 10px 22px;
            font-size: 14px;
            font-weight: 600;
            border-radius: var(--radius-md);
            cursor: pointer;
            transition: all 0.25s ease;
            border: 1px solid transparent;
            text-align: center;
        }
        .btn-primary {
            background-color: var(--primary);
            color: #FFFFFF;
            box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
        }
        .btn-primary:hover {
            background-color: var(--primary-dark);
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
        }
        .btn-accent {
            background-color: var(--accent);
            color: #0F172A;
            font-weight: 700;
        }
        .btn-accent:hover {
            background-color: #D97706;
            color: #fff;
            transform: translateY(-2px);
        }
        .btn-outline-dark {
            background-color: transparent;
            color: #FFFFFF;
            border-color: rgba(255, 255, 255, 0.2);
        }
        .btn-outline-dark:hover {
            background-color: rgba(255, 255, 255, 0.08);
            border-color: #FFFFFF;
        }
        .btn-outline {
            background-color: #FFFFFF;
            color: var(--text-main);
            border-color: var(--border-color);
        }
        .btn-outline:hover {
            border-color: var(--primary);
            color: var(--primary);
            background-color: var(--bg-base);
        }
        .badge {
            display: inline-flex;
            align-items: center;
            padding: 4px 12px;
            border-radius: var(--radius-full);
            font-size: 12px;
            font-weight: 600;
            background: rgba(37, 99, 235, 0.08);
            color: var(--primary);
            margin-bottom: 12px;
        }

        /* 统一 Section 排版 */
        .section-padding {
            padding: 96px 0;
        }
        .section-alt {
            background-color: var(--bg-subtle);
        }
        .section-dark {
            background-color: var(--bg-dark);
            color: #F8FAFC;
        }
        .section-header {
            text-align: center;
            max-width: 760px;
            margin: 0 auto 56px auto;
        }
        .section-title {
            font-size: 32px;
            font-weight: 700;
            line-height: 1.3;
            letter-spacing: -0.5px;
            margin-bottom: 16px;
            color: var(--text-main);
        }
        .section-dark .section-title {
            color: #FFFFFF;
        }
        .section-desc {
            font-size: 16px;
            color: var(--text-muted);
            line-height: 1.7;
        }
        .section-dark .section-desc {
            color: #94A3B8;
        }

        /* Section 1: Hero */
        .hero-section {
            position: relative;
            background: linear-gradient(180deg, #0F172A 0%, #1E293B 100%);
            color: #FFFFFF;
            padding: 80px 0 100px 0;
            overflow: hidden;
        }
        .hero-grid {
            display: grid;
            grid-template-columns: 1.1fr 0.9fr;
            gap: 48px;
            align-items: center;
        }
        .hero-content h1 {
            font-size: 44px;
            font-weight: 800;
            line-height: 1.25;
            margin-bottom: 20px;
            letter-spacing: -1px;
        }
        .hero-content h1 span {
            background: linear-gradient(135deg, #60A5FA 0%, #38BDF8 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .hero-desc {
            font-size: 17px;
            color: #CBD5E1;
            line-height: 1.8;
            margin-bottom: 32px;
        }
        .hero-actions {
            display: flex;
            gap: 16px;
            margin-bottom: 40px;
        }
        .hero-meta-points {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 16px;
            padding-top: 24px;
            border-top: 1px solid rgba(255, 255, 255, 0.1);
        }
        .meta-point-item strong {
            display: block;
            font-size: 18px;
            color: #F8FAFC;
        }
        .meta-point-item span {
            font-size: 13px;
            color: #94A3B8;
        }
        .hero-stage {
            position: relative;
            background: #111827;
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
        }
        .stage-badge-float {
            position: absolute;
            top: 16px;
            right: 16px;
            background: rgba(15, 23, 42, 0.85);
            backdrop-filter: blur(8px);
            padding: 6px 12px;
            border-radius: var(--radius-md);
            font-size: 12px;
            color: var(--accent-cyan);
            border: 1px solid rgba(6, 182, 212, 0.3);
        }

        /* Section 2: About & Technical */
        .about-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 56px;
            align-items: center;
        }
        .about-image-card {
            background: var(--bg-surface);
            border-radius: var(--radius-lg);
            overflow: hidden;
            border: 1px solid var(--border-color);
            box-shadow: var(--shadow-md);
        }
        .tech-spec-list {
            margin-top: 24px;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }
        .tech-spec-item {
            display: flex;
            align-items: flex-start;
            gap: 12px;
        }
        .spec-icon {
            width: 24px;
            height: 24px;
            background: #EFF6FF;
            color: var(--primary);
            border-radius: 6px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 12px;
            flex-shrink: 0;
            margin-top: 2px;
        }

        /* Section 3: 6 Features Grid */
        .grid-3-col {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 28px;
        }
        .feature-card {
            background: var(--bg-surface);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            padding: 32px 28px;
            box-shadow: var(--shadow-sm);
            transition: all 0.3s ease;
        }
        .feature-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-hover);
            border-color: #BFDBFE;
        }
        .feature-icon-box {
            width: 48px;
            height: 48px;
            background: #EFF6FF;
            border-radius: var(--radius-md);
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--primary);
            font-size: 20px;
            font-weight: bold;
            margin-bottom: 20px;
        }
        .feature-card h3 {
            font-size: 19px;
            font-weight: 700;
            margin-bottom: 12px;
            color: var(--text-main);
        }
        .feature-card p {
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.65;
        }

        /* Section 4: Product Matrices */
        .product-card {
            background: var(--bg-surface);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            padding: 32px;
            box-shadow: var(--shadow-sm);
            display: flex;
            flex-direction: column;
            position: relative;
        }
        .product-card.featured {
            border-color: var(--primary);
            box-shadow: 0 12px 30px rgba(37, 99, 235, 0.12);
        }
        .product-tag {
            position: absolute;
            top: -12px;
            right: 24px;
            background: var(--primary);
            color: #fff;
            font-size: 12px;
            font-weight: 600;
            padding: 2px 10px;
            border-radius: 12px;
        }
        .product-title {
            font-size: 22px;
            font-weight: 700;
            margin-bottom: 8px;
        }
        .product-subtitle {
            font-size: 14px;
            color: var(--text-light);
            margin-bottom: 24px;
        }
        .product-img-wrap {
            border-radius: var(--radius-md);
            overflow: hidden;
            margin-bottom: 24px;
            border: 1px solid var(--border-color);
        }
        .product-features-list {
            list-style: none;
            margin-bottom: 32px;
            flex-grow: 1;
        }
        .product-features-list li {
            font-size: 14px;
            color: var(--text-muted);
            padding: 8px 0;
            border-bottom: 1px dashed var(--border-color);
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .product-features-list li::before {
            content: "✓";
            color: var(--primary);
            font-weight: bold;
        }

        /* Section 5: Bento Concept Dark */
        .bento-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            grid-auto-rows: 220px;
            gap: 20px;
        }
        .bento-card {
            background: #131B2E;
            border: 1px solid var(--border-dark);
            border-radius: var(--radius-lg);
            padding: 28px;
            overflow: hidden;
            position: relative;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }
        .bento-col-2 {
            grid-column: span 2;
        }
        .bento-row-2 {
            grid-row: span 2;
        }
        .bento-card h4 {
            font-size: 20px;
            color: #FFFFFF;
            margin-bottom: 8px;
        }
        .bento-card p {
            font-size: 14px;
            color: #94A3B8;
            line-height: 1.6;
        }
        .bento-code-pill {
            font-family: monospace;
            background: rgba(0, 0, 0, 0.4);
            padding: 8px 12px;
            border-radius: 6px;
            font-size: 12px;
            color: var(--accent-cyan);
            border: 1px solid rgba(255, 255, 255, 0.05);
        }

        /* Section 6: Case Studies */
        .grid-2-col {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 32px;
        }
        .case-card {
            background: var(--bg-surface);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow-sm);
        }
        .case-img-box {
            height: 220px;
            overflow: hidden;
        }
        .case-img-box img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }
        .case-body {
            padding: 28px;
        }
        .case-tag {
            font-size: 12px;
            color: var(--primary);
            font-weight: 700;
            text-transform: uppercase;
            margin-bottom: 8px;
            display: block;
        }
        .case-title {
            font-size: 20px;
            font-weight: 700;
            margin-bottom: 12px;
        }
        .case-desc {
            font-size: 14px;
            color: var(--text-muted);
            margin-bottom: 20px;
            line-height: 1.65;
        }
        .case-stats-row {
            display: flex;
            gap: 20px;
            padding-top: 16px;
            border-top: 1px solid var(--border-color);
        }
        .case-stat-val {
            font-size: 18px;
            font-weight: 700;
            color: var(--primary);
        }
        .case-stat-lbl {
            font-size: 12px;
            color: var(--text-light);
        }

        /* Section 7: Metrics Banner */
        .metrics-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
            text-align: center;
        }
        .metric-item {
            padding: 24px;
            background: var(--bg-surface);
            border-radius: var(--radius-lg);
            border: 1px solid var(--border-color);
        }
        .metric-num {
            font-size: 40px;
            font-weight: 800;
            color: var(--primary);
            line-height: 1.1;
            margin-bottom: 8px;
            letter-spacing: -1px;
        }
        .metric-label {
            font-size: 14px;
            color: var(--text-muted);
            font-weight: 500;
        }

        /* Section 8: Testimonials */
        .testimonial-card {
            background: var(--bg-surface);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            padding: 32px;
            box-shadow: var(--shadow-sm);
        }
        .testimonial-rating {
            color: var(--accent);
            margin-bottom: 12px;
            font-size: 14px;
        }
        .testimonial-text {
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.7;
            margin-bottom: 20px;
            font-style: italic;
        }
        .testimonial-author {
            display: flex;
            align-items: center;
            gap: 12px;
        }
        .author-avatar {
            width: 44px;
            height: 44px;
            border-radius: 50%;
            background: #E2E8F0;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            color: var(--primary);
        }
        .author-info h5 {
            font-size: 15px;
            font-weight: 700;
            color: var(--text-main);
        }
        .author-info span {
            font-size: 12px;
            color: var(--text-light);
        }

        /* Section 9: Insights */
        .insight-card {
            background: var(--bg-surface);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            padding: 24px;
            box-shadow: var(--shadow-sm);
        }
        .insight-date {
            font-size: 12px;
            color: var(--text-light);
            margin-bottom: 8px;
        }
        .insight-title {
            font-size: 17px;
            font-weight: 700;
            margin-bottom: 10px;
            color: var(--text-main);
        }
        .insight-desc {
            font-size: 13px;
            color: var(--text-muted);
            line-height: 1.6;
            margin-bottom: 16px;
        }

        /* Section 10: FAQ Accordion */
        .faq-wrap {
            max-width: 860px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }
        .faq-item {
            background: var(--bg-surface);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-md);
            padding: 24px;
        }
        .faq-item summary {
            font-size: 17px;
            font-weight: 700;
            color: var(--text-main);
            cursor: pointer;
            list-style: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .faq-item summary::-webkit-details-marker {
            display: none;
        }
        .faq-item summary::after {
            content: "+";
            font-size: 20px;
            color: var(--primary);
            font-weight: bold;
        }
        .faq-item[open] summary::after {
            content: "−";
        }
        .faq-item p {
            margin-top: 14px;
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.7;
            border-top: 1px solid var(--border-color);
            padding-top: 12px;
        }

        /* Section 11: Guarantee Bar */
        .guarantee-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
        }
        .guarantee-box {
            display: flex;
            align-items: center;
            gap: 16px;
            background: var(--bg-surface);
            border: 1px solid var(--border-color);
            padding: 20px;
            border-radius: var(--radius-md);
        }
        .guarantee-icon {
            width: 40px;
            height: 40px;
            background: #EFF6FF;
            color: var(--primary);
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 18px;
            font-weight: bold;
            flex-shrink: 0;
        }
        .guarantee-text h4 {
            font-size: 15px;
            font-weight: 700;
            margin-bottom: 2px;
        }
        .guarantee-text p {
            font-size: 12px;
            color: var(--text-light);
        }

        /* Section 12: CTA Final */
        .cta-card-box {
            background: linear-gradient(135deg, #1E3A8A 0%, #0F172A 100%);
            border-radius: 20px;
            padding: 64px 48px;
            color: #FFFFFF;
            text-align: center;
            box-shadow: 0 20px 40px rgba(15, 23, 42, 0.2);
        }
        .cta-card-box h2 {
            font-size: 32px;
            font-weight: 800;
            margin-bottom: 16px;
        }
        .cta-card-box p {
            font-size: 16px;
            color: #CBD5E1;
            max-width: 600px;
            margin: 0 auto 32px auto;
            line-height: 1.7;
        }
        .cta-form {
            display: flex;
            justify-content: center;
            gap: 12px;
            max-width: 520px;
            margin: 0 auto;
        }
        .cta-input {
            flex: 1;
            padding: 14px 20px;
            border-radius: var(--radius-md);
            border: 1px solid rgba(255, 255, 255, 0.2);
            background: rgba(255, 255, 255, 0.1);
            color: #FFFFFF;
            font-size: 14px;
            outline: none;
        }
        .cta-input::placeholder {
            color: #94A3B8;
        }

        /* 页脚 Footer */
        .site-footer {
            background-color: var(--bg-dark);
            color: #94A3B8;
            padding: 72px 0 32px 0;
            border-top: 1px solid var(--border-dark);
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 1.5fr repeat(3, 1fr);
            gap: 48px;
            margin-bottom: 48px;
        }
        .footer-col h5 {
            color: #F8FAFC;
            font-size: 15px;
            font-weight: 700;
            margin-bottom: 20px;
        }
        .footer-links {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 10px;
        }
        .footer-links a {
            font-size: 14px;
            color: #94A3B8;
        }
        .footer-links a:hover {
            color: #FFFFFF;
        }
        .footer-bottom {
            padding-top: 32px;
            border-top: 1px solid var(--border-dark);
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 13px;
        }

        /* 响应式媒体查询 */
        @media (max-width: 1024px) {
            .hero-grid, .about-grid {
                grid-template-columns: 1fr;
                gap: 40px;
            }
            .grid-3-col {
                grid-template-columns: repeat(2, 1fr);
            }
            .bento-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .bento-col-2 {
                grid-column: span 2;
            }
            .metrics-grid, .guarantee-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .footer-grid {
                grid-template-columns: 1fr 1fr;
            }
        }

        @media (max-width: 767px) {
            .section-padding {
                padding: 56px 0;
            }
            .hero-content h1 {
                font-size: 32px;
            }
            .section-title {
                font-size: 26px;
            }
            .grid-3-col, .grid-2-col, .bento-grid, .metrics-grid, .guarantee-grid {
                grid-template-columns: 1fr;
            }
            .bento-col-2, .bento-row-2 {
                grid-column: span 1;
                grid-row: span 1;
            }
            .main-nav {
                display: none;
            }
            .hero-actions {
                flex-direction: column;
            }
            .hero-meta-points {
                grid-template-columns: 1fr;
            }
            .cta-form {
                flex-direction: column;
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 32px;
            }
            .footer-bottom {
                flex-direction: column;
                gap: 12px;
                text-align: center;
            }
        }