/* CSS Reset & Variable Design - 黑白胶片摄影风格 */
        :root {
            --bg-color: #F8F9FA;
            --surface-color: #FFFFFF;
            --text-primary: #111111;
            --text-secondary: #555555;
            --text-muted: #888888;
            --border-color: #E2E8F0;
            --border-dark: #111111;
            --accent-color: #000000;
            --accent-hover: #333333;
            --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
            --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
            --max-width: 1200px;
            --font-serif: "Georgia", "Times New Roman", "Source Han Serif CN", serif;
            --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
        }

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

        html {
            scroll-behavior: smooth;
            font-size: 16px;
        }

        body {
            font-family: var(--font-sans);
            background-color: var(--bg-color);
            color: var(--text-primary);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }

        h1, h2, h3, h4, h5, h6 {
            font-family: var(--font-sans);
            font-weight: 700;
            color: var(--text-primary);
            line-height: 1.25;
            letter-spacing: -0.02em;
        }

        a {
            color: inherit;
            text-decoration: none;
            transition: all 0.3s ease;
        }

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

        section {
            padding: 100px 0;
            border-bottom: 1px solid var(--border-color);
        }

        /* Global Header (Navigation) */
        header {
            position: sticky;
            top: 0;
            background-color: rgba(248, 249, 250, 0.95);
            backdrop-filter: blur(10px);
            border-bottom: 1px solid var(--border-color);
            z-index: 1000;
            transition: background-color 0.3s;
        }
        
        .nav-wrapper {
            display: flex;
            justify-content: space-between;
            align-items: center;
            height: 70px;
        }

        .logo-area {
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .ai-page-logo {
            max-height: 40px;
            filter: grayscale(100%);
        }

        .logo-text {
            font-family: var(--font-serif);
            font-size: 1.4rem;
            font-weight: 800;
            letter-spacing: 0.1em;
            color: var(--text-primary);
        }

        .nav-menu {
            display: flex;
            gap: 24px;
            list-style: none;
        }

        .nav-link {
            font-size: 0.9rem;
            font-weight: 500;
            color: var(--text-secondary);
            letter-spacing: 0.05em;
        }

        .nav-link:hover {
            color: var(--text-primary);
        }

        .nav-cta {
            display: inline-block;
            padding: 8px 18px;
            background-color: var(--accent-color);
            color: #fff !important;
            font-size: 0.85rem;
            font-weight: 600;
            letter-spacing: 0.05em;
            border-radius: 0;
            transition: background-color 0.3s;
        }

        .nav-cta:hover {
            background-color: var(--accent-hover);
        }

        .menu-toggle {
            display: none;
            flex-direction: column;
            gap: 6px;
            cursor: pointer;
            background: none;
            border: none;
        }

        .menu-toggle span {
            width: 25px;
            height: 2px;
            background-color: var(--text-primary);
            transition: 0.3s;
        }

        /* Hero Section (No Images allowed) */
        .hero {
            padding: 120px 0 100px 0;
            background-color: #FFFFFF;
            text-align: center;
            border-bottom: 2px solid var(--border-dark);
        }

        .hero-badge {
            display: inline-block;
            padding: 4px 12px;
            border: 1px solid var(--text-primary);
            font-size: 0.75rem;
            font-weight: 700;
            letter-spacing: 0.15em;
            margin-bottom: 24px;
            text-transform: uppercase;
        }

        .hero-title {
            font-family: var(--font-serif);
            font-size: 3rem;
            font-weight: 900;
            letter-spacing: -0.03em;
            max-width: 900px;
            margin: 0 auto 24px auto;
            color: var(--text-primary);
        }

        .hero-desc {
            font-size: 1.15rem;
            color: var(--text-secondary);
            max-width: 650px;
            margin: 0 auto 40px auto;
            font-weight: 300;
        }

        .hero-actions {
            display: flex;
            justify-content: center;
            gap: 16px;
        }

        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 14px 32px;
            font-size: 0.95rem;
            font-weight: 600;
            letter-spacing: 0.05em;
            transition: all 0.3s ease;
            cursor: pointer;
        }

        .btn-primary {
            background-color: var(--accent-color);
            color: #fff;
            border: 1px solid var(--accent-color);
        }

        .btn-primary:hover {
            background-color: var(--accent-hover);
            border-color: var(--accent-hover);
        }

        .btn-secondary {
            background-color: transparent;
            color: var(--text-primary);
            border: 1px solid var(--text-primary);
        }

        .btn-secondary:hover {
            background-color: var(--text-primary);
            color: #fff;
        }

        /* Section Typography & Titles */
        .section-header {
            max-width: 700px;
            margin-bottom: 60px;
        }

        .section-tag {
            font-size: 0.75rem;
            font-weight: 700;
            letter-spacing: 0.2em;
            text-transform: uppercase;
            color: var(--text-muted);
            margin-bottom: 12px;
            display: block;
        }

        .section-title {
            font-family: var(--font-serif);
            font-size: 2.2rem;
            font-weight: 800;
            margin-bottom: 16px;
        }

        .section-intro {
            font-size: 1rem;
            color: var(--text-secondary);
        }

        /* About Section (Software/Platform Intro) */
        .about-grid {
            display: grid;
            grid-template-columns: 1.2fr 0.8fr;
            gap: 60px;
            align-items: center;
        }

        .about-text h3 {
            font-size: 1.5rem;
            margin-bottom: 20px;
        }

        .about-text p {
            color: var(--text-secondary);
            margin-bottom: 24px;
        }

        .feature-bullets {
            list-style: none;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 16px;
        }

        .feature-bullets li {
            position: relative;
            padding-left: 24px;
            font-size: 0.95rem;
            color: var(--text-primary);
            font-weight: 600;
        }

        .feature-bullets li::before {
            content: "■";
            position: absolute;
            left: 0;
            color: var(--accent-color);
        }

        /* Data Cards Grid */
        .data-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
            margin-top: 40px;
            background-color: #FFFFFF;
            border: 1px solid var(--border-color);
            padding: 30px;
        }

        .data-card {
            text-align: center;
            border-right: 1px solid var(--border-color);
        }

        .data-card:last-child {
            border-right: none;
        }

        .data-val {
            font-family: var(--font-serif);
            font-size: 2.5rem;
            font-weight: 800;
            color: var(--text-primary);
            margin-bottom: 8px;
        }

        .data-label {
            font-size: 0.85rem;
            color: var(--text-secondary);
            letter-spacing: 0.05em;
        }

        /* Service Cards */
        .service-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 30px;
        }

        .service-card {
            background-color: var(--surface-color);
            border: 1px solid var(--border-color);
            padding: 40px;
            transition: all 0.4s ease;
        }

        .service-card:hover {
            border-color: var(--border-dark);
            transform: translateY(-5px);
        }

        .service-num {
            font-family: var(--font-serif);
            font-size: 1.5rem;
            font-style: italic;
            color: var(--text-muted);
            margin-bottom: 24px;
        }

        .service-title {
            font-size: 1.25rem;
            margin-bottom: 16px;
        }

        .service-desc {
            font-size: 0.9rem;
            color: var(--text-secondary);
            margin-bottom: 24px;
        }

        .service-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
        }

        .service-tag-item {
            font-size: 0.75rem;
            background-color: var(--bg-color);
            padding: 4px 10px;
            color: var(--text-secondary);
            border: 1px solid var(--border-color);
        }

        /* Workflow Steps */
        .workflow-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
            position: relative;
        }

        .workflow-step {
            background-color: #FFF;
            border: 1px solid var(--border-color);
            padding: 30px;
            position: relative;
        }

        .workflow-step-num {
            font-family: var(--font-serif);
            font-size: 2.5rem;
            font-weight: 800;
            color: var(--border-color);
            position: absolute;
            top: 20px;
            right: 20px;
            line-height: 1;
        }

        .workflow-step-title {
            font-size: 1.15rem;
            margin-bottom: 12px;
            margin-top: 20px;
            position: relative;
            z-index: 2;
        }

        .workflow-step-desc {
            font-size: 0.85rem;
            color: var(--text-secondary);
            position: relative;
            z-index: 2;
        }

        /* Solutions Section */
        .solutions-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 40px;
        }

        .solution-card {
            border: 1px solid var(--border-color);
            background-color: #fff;
            padding: 40px;
        }

        .solution-title {
            font-size: 1.35rem;
            margin-bottom: 16px;
            border-left: 3px solid var(--accent-color);
            padding-left: 12px;
        }

        .solution-body {
            font-size: 0.95rem;
            color: var(--text-secondary);
        }

        /* Tech Standards & Network */
        .flex-split {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 60px;
        }

        .map-wrapper {
            background-color: #FFF;
            border: 1px solid var(--border-color);
            padding: 30px;
            display: flex;
            flex-direction: column;
            justify-content: center;
        }

        .network-list {
            list-style: none;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 16px;
            margin-top: 24px;
        }

        .network-list li {
            font-size: 0.9rem;
            color: var(--text-secondary);
            padding-left: 16px;
            position: relative;
        }

        .network-list li::before {
            content: "•";
            position: absolute;
            left: 0;
            color: var(--text-primary);
        }

        /* Cases Center (Image Gallery) */
        .case-gallery {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }

        .case-item {
            background-color: #fff;
            border: 1px solid var(--border-color);
            overflow: hidden;
            transition: all 0.3s;
        }

        .case-item:hover {
            border-color: var(--border-dark);
        }

        .case-img-box {
            position: relative;
            background-color: #f0f0f0;
            aspect-ratio: 16 / 10;
            overflow: hidden;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .case-img-box img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            filter: grayscale(100%);
            transition: transform 0.5s ease, filter 0.5s ease;
        }

        .case-item:hover .case-img-box img {
            filter: grayscale(0%);
            transform: scale(1.05);
        }

        .case-info {
            padding: 24px;
        }

        .case-cat {
            font-size: 0.75rem;
            color: var(--text-muted);
            text-transform: uppercase;
            letter-spacing: 0.05em;
            margin-bottom: 8px;
        }

        .case-name {
            font-size: 1.1rem;
            margin-bottom: 8px;
        }

        .case-desc {
            font-size: 0.85rem;
            color: var(--text-secondary);
        }

        /* Compare Evaluation Table */
        .eval-section {
            background-color: #FFFFFF;
        }

        .eval-summary {
            display: flex;
            align-items: center;
            gap: 24px;
            margin-bottom: 40px;
            background: var(--bg-color);
            padding: 24px;
            border-left: 4px solid var(--accent-color);
        }

        .score-box {
            font-family: var(--font-serif);
            font-size: 2.8rem;
            font-weight: 900;
        }

        .star-box {
            font-size: 1.25rem;
            letter-spacing: 2px;
        }

        .eval-intro {
            font-size: 0.95rem;
            color: var(--text-secondary);
        }

        .table-responsive {
            width: 100%;
            overflow-x: auto;
            border: 1px solid var(--border-color);
        }

        .eval-table {
            width: 100%;
            border-collapse: collapse;
            text-align: left;
            min-width: 600px;
            font-size: 0.9rem;
        }

        .eval-table th, .eval-table td {
            padding: 16px 24px;
            border-bottom: 1px solid var(--border-color);
        }

        .eval-table th {
            background-color: var(--bg-color);
            font-weight: 700;
        }

        .eval-table tr:last-child td {
            border-bottom: none;
        }

        .eval-table tr:hover {
            background-color: rgba(0, 0, 0, 0.01);
        }

        .tag-highlight {
            background-color: var(--accent-color);
            color: #FFF;
            padding: 2px 8px;
            font-size: 0.75rem;
            font-weight: 600;
        }

        /* Token Pricing & Models */
        .token-header {
            display: flex;
            justify-content: space-between;
            align-items: flex-end;
            margin-bottom: 40px;
        }

        .token-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }

        .token-card {
            background: #FFF;
            border: 1px solid var(--border-color);
            padding: 30px;
            text-align: center;
        }

        .token-card.featured {
            border-color: var(--border-dark);
            box-shadow: var(--shadow-md);
        }

        .token-model-name {
            font-size: 1.2rem;
            margin-bottom: 16px;
        }

        .token-price {
            font-family: var(--font-serif);
            font-size: 2.2rem;
            font-weight: 800;
            margin-bottom: 8px;
        }

        .token-unit {
            font-size: 0.8rem;
            color: var(--text-muted);
            margin-bottom: 20px;
        }

        .model-list-wrapped {
            font-size: 0.8rem;
            color: var(--text-secondary);
            border-top: 1px solid var(--border-color);
            padding-top: 16px;
            line-height: 1.8;
        }

        /* Training & Certification */
        .training-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }

        .training-card {
            border: 1px solid var(--border-color);
            background-color: #fff;
            padding: 30px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .training-title {
            font-size: 1.15rem;
            margin-bottom: 16px;
        }

        .training-desc {
            font-size: 0.85rem;
            color: var(--text-secondary);
            margin-bottom: 24px;
        }

        .cert-info {
            font-size: 0.75rem;
            color: var(--text-muted);
            border-top: 1px dashed var(--border-color);
            padding-top: 16px;
        }

        /* Smart Matching Form Section */
        .form-section {
            background-color: var(--surface-color);
        }

        .form-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 60px;
            align-items: start;
        }

        .form-info h3 {
            font-family: var(--font-serif);
            font-size: 1.8rem;
            margin-bottom: 20px;
        }

        .form-info p {
            color: var(--text-secondary);
            margin-bottom: 30px;
        }

        .matching-form {
            background: var(--bg-color);
            padding: 40px;
            border: 1px solid var(--border-color);
        }

        .form-group {
            margin-bottom: 20px;
        }

        .form-group label {
            display: block;
            font-size: 0.85rem;
            font-weight: 600;
            margin-bottom: 8px;
            color: var(--text-primary);
        }

        .form-control {
            width: 100%;
            padding: 12px;
            border: 1px solid var(--border-color);
            background-color: #FFFFFF;
            font-family: var(--font-sans);
            font-size: 0.9rem;
            color: var(--text-primary);
            transition: border-color 0.3s;
        }

        .form-control:focus {
            outline: none;
            border-color: var(--border-dark);
        }

        /* Help Center / FAQ Accordions */
        .help-grid {
            display: grid;
            grid-template-columns: 1fr 2fr;
            gap: 60px;
        }

        .help-sidebar {
            position: sticky;
            top: 100px;
        }

        .wiki-card {
            background: #fff;
            border: 1px solid var(--border-color);
            padding: 30px;
            margin-bottom: 24px;
        }

        .wiki-title {
            font-size: 1.1rem;
            margin-bottom: 12px;
            font-weight: 700;
        }

        .wiki-desc {
            font-size: 0.8rem;
            color: var(--text-secondary);
            line-height: 1.6;
        }

        .faq-list {
            display: flex;
            flex-direction: column;
            gap: 16px;
        }

        .faq-item {
            border: 1px solid var(--border-color);
            background-color: #FFFFFF;
        }

        .faq-question {
            width: 100%;
            padding: 20px 24px;
            text-align: left;
            background: none;
            border: none;
            font-size: 1rem;
            font-weight: 600;
            display: flex;
            justify-content: space-between;
            align-items: center;
            cursor: pointer;
        }

        .faq-question::after {
            content: "+";
            font-size: 1.25rem;
            font-weight: 300;
            transition: transform 0.3s;
        }

        .faq-item.active .faq-question::after {
            transform: rotate(45deg);
        }

        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease-out;
        }

        .faq-answer-inner {
            padding: 0 24px 20px 24px;
            font-size: 0.9rem;
            color: var(--text-secondary);
            border-top: 1px solid transparent;
        }

        .faq-item.active .faq-answer-inner {
            border-top-color: var(--border-color);
        }

        /* User Reviews */
        .reviews-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }

        .review-card {
            background-color: #FFFFFF;
            border: 1px solid var(--border-color);
            padding: 30px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .review-quote {
            font-size: 0.9rem;
            color: var(--text-secondary);
            margin-bottom: 24px;
            position: relative;
            font-style: italic;
        }

        .review-user {
            display: flex;
            align-items: center;
            gap: 12px;
            border-top: 1px solid var(--border-color);
            padding-top: 16px;
        }

        .user-info h4 {
            font-size: 0.9rem;
            font-weight: 700;
        }

        .user-info p {
            font-size: 0.75rem;
            color: var(--text-muted);
        }

        /* News & Knowledge base */
        .news-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }

        .news-card {
            border: 1px solid var(--border-color);
            background: #FFF;
            padding: 30px;
        }

        .news-meta {
            font-size: 0.75rem;
            color: var(--text-muted);
            margin-bottom: 12px;
        }

        .news-title {
            font-size: 1.1rem;
            margin-bottom: 16px;
            line-height: 1.4;
        }

        .news-link {
            font-size: 0.85rem;
            font-weight: 600;
            color: var(--text-primary);
            display: inline-flex;
            align-items: center;
            gap: 4px;
        }

        .news-link:hover {
            text-decoration: underline;
        }

        /* Footer & Links */
        footer {
            background-color: #111111;
            color: #FFFFFF;
            padding: 80px 0 40px 0;
            font-size: 0.85rem;
        }

        footer a {
            color: #888888;
        }

        footer a:hover {
            color: #FFFFFF;
        }

        .footer-grid {
            display: grid;
            grid-template-columns: 1.2fr 0.8fr 1fr;
            gap: 60px;
            margin-bottom: 60px;
        }

        .footer-brand h4 {
            font-family: var(--font-serif);
            font-size: 1.4rem;
            color: #FFF;
            margin-bottom: 16px;
        }

        .footer-brand p {
            color: #888888;
            margin-bottom: 24px;
            line-height: 1.6;
        }

        .footer-nav h5, .footer-contact h5 {
            color: #FFF;
            margin-bottom: 20px;
            font-size: 0.95rem;
            letter-spacing: 0.05em;
        }

        .footer-links {
            list-style: none;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 12px;
        }

        .footer-contact-info {
            display: flex;
            flex-direction: column;
            gap: 12px;
            color: #888888;
        }

        .footer-qr {
            display: flex;
            gap: 20px;
            align-items: center;
            margin-top: 20px;
        }

        .footer-qr img {
            width: 80px;
            height: 80px;
            background-color: #FFF;
            padding: 4px;
        }

        .footer-qr-label {
            font-size: 0.75rem;
            color: #888888;
            line-height: 1.4;
        }

        /* Friend Links */
        .friend-links-box {
            border-top: 1px solid #222;
            padding: 24px 0;
            display: flex;
            flex-wrap: wrap;
            gap: 16px;
            font-size: 0.75rem;
            color: #555;
        }

        .friend-links-box a {
            color: #555;
        }

        .friend-links-box a:hover {
            color: #888;
        }

        /* Footer Copyright */
        .footer-copyright {
            border-top: 1px solid #222;
            padding-top: 24px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            color: #555;
            font-size: 0.75rem;
        }

        /* Float Customer Service */
        .float-cs {
            position: fixed;
            bottom: 30px;
            right: 30px;
            background-color: #FFFFFF;
            border: 1px solid var(--border-dark);
            padding: 12px;
            box-shadow: var(--shadow-md);
            z-index: 999;
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 8px;
            cursor: pointer;
            transition: transform 0.3s;
        }

        .float-cs:hover {
            transform: translateY(-5px);
        }

        .float-cs img {
            width: 70px;
            height: 70px;
        }

        .float-cs span {
            font-size: 0.7rem;
            font-weight: 700;
            letter-spacing: 0.05em;
        }

        /* Responsive Breakpoints */
        @media (max-width: 1024px) {
            .about-grid, .form-grid, .help-grid, .flex-split {
                grid-template-columns: 1fr;
                gap: 40px;
            }
            .data-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .service-grid, .workflow-grid, .case-gallery, .token-grid, .training-grid, .reviews-grid, .news-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 40px;
            }
            .help-sidebar {
                position: static;
            }
        }

        @media (max-width: 768px) {
            .nav-menu {
                display: none;
                flex-direction: column;
                position: absolute;
                top: 70px;
                left: 0;
                width: 100%;
                background-color: var(--surface-color);
                border-bottom: 1px solid var(--border-color);
                padding: 20px;
                gap: 16px;
            }
            .nav-menu.active {
                display: flex;
            }
            .menu-toggle {
                display: flex;
            }
            .hero-title {
                font-size: 2.2rem;
            }
            .data-grid, .service-grid, .workflow-grid, .case-gallery, .token-grid, .training-grid, .reviews-grid, .news-grid, .solutions-grid {
                grid-template-columns: 1fr;
            }
        }