:root {
            --gtmamk-primary: #ff6600;
            --gtmamk-secondary: #2b3d51;
            --gtmamk-accent: #4a90e2;
            --gtmamk-bg: #f8fafc;
            --gtmamk-text: #1e293b;
            --gtmamk-text-light: #64748b;
            --gtmamk-white: #ffffff;
            --gtmamk-container-width: 1400px;
            --gtmamk-radius: 16px;
        }

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

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
            background-color: var(--gtmamk-bg);
            color: var(--gtmamk-text);
            line-height: 1.6;
            overflow-x: hidden;
        }

        /* 导航栏 */
        .gtmamk-header {
            position: fixed;
            top: 24px;
            left: 50%;
            transform: translateX(-50%);
            width: calc(100% - 48px);
            max-width: var(--gtmamk-container-width);
            height: 72px;
            background: rgba(255, 255, 255, 0.85);
            backdrop-filter: blur(12px);
            border: 1px solid rgba(255, 255, 255, 0.3);
            border-radius: 40px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 0 32px;
            z-index: 1000;
            box-shadow: 0 10px 30px rgba(0,0,0,0.05);
        }

        .gtmamk-logo {
            display: flex;
            align-items: center;
            min-width: 0;
        }

        .gtmamk-logo img {
            height: 32px;
            width: auto;
        }

        .gtmamk-nav {
            display: flex;
            flex-wrap: wrap;
            gap: 24px;
            min-width: 0;
        }

        .gtmamk-nav a {
            text-decoration: none;
            color: var(--gtmamk-secondary);
            font-weight: 500;
            font-size: 0.95rem;
            transition: color 0.3s ease;
            white-space: nowrap;
        }

        .gtmamk-nav a:hover {
            color: var(--gtmamk-primary);
        }

        /* Hero 区 - 独特阶梯布局 */
        .gtmamk-hero {
            padding-top: 160px;
            padding-bottom: 96px;
            background: linear-gradient(135deg, #fff5f0 0%, #eef6ff 100%);
            display: flex;
            flex-direction: column;
            align-items: center;
            text-align: center;
            position: relative;
            overflow: hidden;
        }

        .gtmamk-hero-content {
            max-width: 900px;
            padding: 0 24px;
            z-index: 2;
            word-break: break-word;
        }

        .gtmamk-hero-title {
            font-size: clamp(2.5rem, 5vw + 1rem, 4.5rem);
            font-weight: 800;
            line-height: 1.2;
            color: var(--gtmamk-secondary);
            margin-bottom: 24px;
            word-break: keep-all;
        }

        .gtmamk-hero-subtitle {
            font-size: clamp(1.1rem, 1.5vw + 0.5rem, 1.5rem);
            color: var(--gtmamk-text-light);
            margin-bottom: 48px;
            max-width: 700px;
            margin-left: auto;
            margin-right: auto;
        }

        .gtmamk-download-btn {
            display: inline-flex;
            align-items: center;
            background: linear-gradient(90deg, #ff8c42, #ff6600);
            color: white;
            padding: 20px 64px;
            border-radius: 50px;
            font-size: 1.25rem;
            font-weight: 600;
            text-decoration: none;
            box-shadow: 0 20px 40px rgba(255, 102, 0, 0.25);
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }

        .gtmamk-download-btn:hover {
            transform: translateY(-5px);
            box-shadow: 0 25px 50px rgba(255, 102, 0, 0.35);
        }

        /* 专业词库区 - 侧边交错布局 */
        .gtmamk-lexicon-section {
            padding: 96px 0;
            background: var(--gtmamk-white);
        }

        .gtmamk-container {
            max-width: var(--gtmamk-container-width);
            margin: 0 auto;
            padding: 0 48px;
        }

        .gtmamk-section-header {
            margin-bottom: 64px;
            text-align: center;
        }

        .gtmamk-lexicon-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
            gap: 32px;
        }

        .gtmamk-lexicon-card {
            background: var(--gtmamk-bg);
            padding: 40px;
            border-radius: var(--gtmamk-radius);
            border: 1px solid #e2e8f0;
            transition: all 0.3s ease;
            display: flex;
            flex-direction: column;
            min-width: 0;
            word-break: break-word;
        }

        .gtmamk-lexicon-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 20px 40px rgba(0,0,0,0.08);
            border-color: var(--gtmamk-primary);
        }

        .gtmamk-industry-tag {
            display: inline-block;
            background: rgba(255, 102, 0, 0.1);
            color: var(--gtmamk-primary);
            padding: 4px 16px;
            border-radius: 20px;
            font-size: 0.85rem;
            font-weight: 700;
            margin-bottom: 16px;
        }

        .gtmamk-lexicon-card h3 {
            font-size: 1.75rem;
            margin-bottom: 16px;
            color: var(--gtmamk-secondary);
        }

        .gtmamk-lexicon-depth {
            color: var(--gtmamk-text-light);
            font-size: 1rem;
            margin-bottom: 24px;
        }

        .gtmamk-lexicon-samples {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
            margin-top: auto;
        }

        .gtmamk-sample-pill {
            background: var(--gtmamk-white);
            border: 1px solid #cbd5e1;
            padding: 6px 12px;
            border-radius: 6px;
            font-size: 0.85rem;
            color: var(--gtmamk-text);
        }

        /* 特色功能区 - 左右图文 */
        .gtmamk-feature-row {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 64px;
            padding: 80px 0;
        }

        .gtmamk-feature-row:nth-child(even) {
            flex-direction: row-reverse;
        }

        .gtmamk-feature-text {
            flex: 1;
            min-width: 300px;
            word-break: break-word;
        }

        .gtmamk-feature-visual {
            flex: 1.2;
            min-width: 300px;
            background: linear-gradient(45deg, #f1f5f9, #e2e8f0);
            height: 400px;
            border-radius: 24px;
            display: flex;
            align-items: center;
            justify-content: center;
            position: relative;
            box-shadow: inset 0 0 50px rgba(255,255,255,0.5);
        }

        .gtmamk-feature-visual::after {
            content: "功能演示占位";
            color: #94a3b8;
            font-weight: 600;
        }

        .gtmamk-feature-title {
            font-size: clamp(1.8rem, 3vw, 2.5rem);
            margin-bottom: 24px;
            color: var(--gtmamk-secondary);
        }

        /* 动态更新区 */
        .gtmamk-dynamic-section {
            background: #1e293b;
            color: white;
            padding: 96px 0;
        }

        .gtmamk-dynamic-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: 24px;
        }

        .gtmamk-dynamic-item {
            background: rgba(255, 255, 255, 0.05);
            padding: 24px;
            border-radius: 12px;
            transition: background 0.3s ease;
        }

        .gtmamk-dynamic-item:hover {
            background: rgba(255, 255, 255, 0.1);
        }

        /* 页脚 */
        .gtmamk-footer {
            background: #0f172a;
            color: #94a3b8;
            padding: 80px 0 40px;
        }

        .gtmamk-footer-grid {
            display: flex;
            flex-wrap: wrap;
            gap: 48px;
            margin-bottom: 64px;
        }

        .gtmamk-footer-col {
            flex: 1;
            min-width: 200px;
        }

        .gtmamk-footer-brand {
            font-size: 1.5rem;
            color: white;
            font-weight: 700;
            margin-bottom: 24px;
        }

        .gtmamk-footer-links {
            list-style: none;
        }

        .gtmamk-footer-links li {
            margin-bottom: 12px;
        }

        .gtmamk-footer-links a {
            color: #94a3b8;
            text-decoration: none;
            transition: color 0.3s ease;
        }

        .gtmamk-footer-links a:hover {
            color: var(--gtmamk-primary);
        }

        .gtmamk-copyright {
            padding-top: 40px;
            border-top: 1px solid rgba(255, 255, 255, 0.1);
            text-align: center;
            font-size: 0.85rem;
        }

        /* 响应式适配 */
        @media (max-width: 768px) {
            .gtmamk-header {
                top: 0;
                width: 100%;
                border-radius: 0;
                padding: 0 16px;
            }
            .gtmamk-nav {
                display: none; /* 简化移动端，实际项目中应使用汉堡菜单 */
            }
            .gtmamk-hero {
                padding-top: 120px;
            }
            .gtmamk-container {
                padding: 0 24px;
            }
            .gtmamk-feature-row {
                gap: 32px;
            }
            .gtmamk-lexicon-grid {
                grid-template-columns: 1fr;
            }
        }