:root {
            --umkciz-primary: #FF6600;
            --umkciz-primary-dark: #E65C00;
            --umkciz-secondary: #4A90E2;
            --umkciz-bg-light: #F8FAFC;
            --umkciz-text-dark: #1E293B;
            --umkciz-text-muted: #64748B;
            --umkciz-white: #FFFFFF;
            --umkciz-gradient: linear-gradient(135deg, #FF6600 0%, #FF8533 100%);
            --umkciz-shadow: 0 10px 30px rgba(0, 0, 0, 0.05);
            --umkciz-radius: 16px;
        }

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

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            background-color: var(--umkciz-bg-light);
            color: var(--umkciz-text-dark);
            line-height: 1.6;
            overflow-x: hidden;
        }

        /* 布局容器 */
        .umkciz-container {
            max-width: 1300px;
            margin: 0 auto;
            padding: 0 24px;
            width: 100%;
        }

        /* 导航栏 */
        .umkciz-header {
            position: sticky;
            top: 0;
            z-index: 1000;
            background: rgba(255, 255, 255, 0.85);
            backdrop-filter: blur(15px);
            border-bottom: 1px solid rgba(0, 0, 0, 0.05);
            padding: 12px 0;
        }

        .umkciz-nav-wrapper {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
        }

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

        .umkciz-logo img {
            height: 36px;
            width: auto;
        }

        .umkciz-nav-menu {
            display: flex;
            flex-wrap: wrap;
            list-style: none;
            gap: 8px;
            min-width: 0;
        }

        .umkciz-nav-item a {
            text-decoration: none;
            color: var(--umkciz-text-dark);
            padding: 8px 16px;
            border-radius: 30px;
            font-size: 15px;
            font-weight: 500;
            transition: all 0.3s ease;
            white-space: nowrap;
        }

        .umkciz-nav-item a:hover {
            color: var(--umkciz-primary);
            background: rgba(255, 102, 0, 0.05);
        }

        .umkciz-nav-item a.active {
            background: var(--umkciz-primary);
            color: var(--umkciz-white);
        }

        /* Hero 区块 - 独特非对称布局 */
        .umkciz-hero {
            padding: 96px 0 64px;
            background: radial-gradient(circle at 80% 20%, rgba(255, 102, 0, 0.05) 0%, transparent 40%);
            position: relative;
            overflow: hidden;
        }

        .umkciz-hero-grid {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 48px;
        }

        .umkciz-hero-content {
            flex: 1;
            min-width: 320px;
            word-break: keep-all;
        }

        .umkciz-hero-content h1 {
            font-size: clamp(2rem, 4vw + 1rem, 3.5rem);
            line-height: 1.2;
            margin-bottom: 24px;
            font-weight: 800;
            color: var(--umkciz-text-dark);
        }

        .umkciz-hero-content p {
            font-size: clamp(1rem, 1.2vw + 0.5rem, 1.25rem);
            color: var(--umkciz-text-muted);
            margin-bottom: 40px;
            max-width: 600px;
        }

        .umkciz-search-box {
            background: var(--umkciz-white);
            padding: 8px;
            border-radius: 50px;
            display: flex;
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
            border: 1px solid rgba(0, 0, 0, 0.05);
            max-width: 500px;
        }

        .umkciz-search-box input {
            flex: 1;
            border: none;
            padding: 12px 24px;
            outline: none;
            font-size: 16px;
            background: transparent;
        }

        .umkciz-search-btn {
            background: var(--umkciz-primary);
            color: var(--umkciz-white);
            border: none;
            padding: 12px 32px;
            border-radius: 40px;
            cursor: pointer;
            font-weight: 600;
            transition: background 0.3s;
        }

        .umkciz-search-btn:hover {
            background: var(--umkciz-primary-dark);
        }

        /* 细胞词库分类 - 瀑布流/网格 */
        .umkciz-section {
            padding: 80px 0;
        }

        .umkciz-section-title {
            text-align: center;
            margin-bottom: 48px;
        }

        .umkciz-section-title h2 {
            font-size: 2.5rem;
            margin-bottom: 16px;
        }

        .umkciz-category-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 32px;
        }

        .umkciz-card {
            background: var(--umkciz-white);
            border-radius: var(--umkciz-radius);
            padding: 32px;
            transition: all 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
            border: 1px solid rgba(0, 0, 0, 0.03);
            display: flex;
            flex-direction: column;
            position: relative;
            overflow: hidden;
            min-width: 0;
        }

        .umkciz-card:hover {
            transform: translateY(-8px);
            box-shadow: 0 30px 60px rgba(0, 0, 0, 0.1);
        }

        .umkciz-card-icon {
            width: 64px;
            height: 64px;
            background: rgba(255, 102, 0, 0.1);
            border-radius: 16px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 24px;
            margin-bottom: 24px;
            color: var(--umkciz-primary);
        }

        .umkciz-card h3 {
            font-size: 1.5rem;
            margin-bottom: 12px;
            word-break: keep-all;
        }

        .umkciz-card p {
            color: var(--umkciz-text-muted);
            margin-bottom: 24px;
            font-size: 0.95rem;
            word-break: break-word;
        }

        .umkciz-card-stats {
            margin-top: auto;
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding-top: 20px;
            border-top: 1px dashed #eee;
        }

        .umkciz-dl-count {
            font-size: 14px;
            color: var(--umkciz-text-muted);
        }

        .umkciz-btn-sm {
            padding: 8px 20px;
            border-radius: 8px;
            background: #F1F5F9;
            color: var(--umkciz-text-dark);
            text-decoration: none;
            font-weight: 600;
            font-size: 14px;
            transition: all 0.2s;
        }

        .umkciz-btn-sm:hover {
            background: var(--umkciz-primary);
            color: var(--umkciz-white);
        }

        /* 热门下载区块 - 动态内容 */
        .umkciz-hot-lexicon {
            background: #111827;
            color: var(--umkciz-white);
            border-radius: 40px;
            padding: 64px;
            margin: 40px 24px;
        }

        .umkciz-hot-lexicon h2 {
            color: var(--umkciz-white);
            margin-bottom: 40px;
        }

        .umkciz-hot-list {
            display: flex;
            flex-wrap: wrap;
            gap: 20px;
        }

        .umkciz-hot-item {
            flex: 1;
            min-width: 200px;
            background: rgba(255, 255, 255, 0.05);
            padding: 24px;
            border-radius: 20px;
            border: 1px solid rgba(255, 255, 255, 0.1);
            transition: background 0.3s;
        }

        .umkciz-hot-item:hover {
            background: rgba(255, 255, 255, 0.1);
        }

        .umkciz-hot-item h4 {
            margin-bottom: 8px;
            font-size: 18px;
        }

        /* 步骤引导 */
        .umkciz-steps {
            display: flex;
            flex-wrap: wrap;
            gap: 40px;
            margin-top: 48px;
        }

        .umkciz-step-item {
            flex: 1;
            min-width: 240px;
            text-align: center;
        }

        .umkciz-step-number {
            width: 50px;
            height: 50px;
            background: var(--umkciz-primary);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 20px;
            font-weight: bold;
            font-size: 20px;
            box-shadow: 0 10px 20px rgba(255, 102, 0, 0.3);
        }

        /* 页脚 */
        .umkciz-footer {
            background: var(--umkciz-white);
            padding: 80px 0 40px;
            border-top: 1px solid #EEF2F6;
        }

        .umkciz-footer-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 48px;
            margin-bottom: 64px;
        }

        .umkciz-footer-brand h4 {
            font-size: 1.5rem;
            color: var(--umkciz-primary);
            margin-bottom: 16px;
        }

        .umkciz-footer-links h5 {
            margin-bottom: 24px;
            font-size: 18px;
        }

        .umkciz-footer-links ul {
            list-style: none;
        }

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

        .umkciz-footer-links a {
            text-decoration: none;
            color: var(--umkciz-text-muted);
            transition: color 0.3s;
        }

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

        .umkciz-copyright {
            text-align: center;
            padding-top: 40px;
            border-top: 1px solid #F1F5F9;
            color: var(--umkciz-text-muted);
            font-size: 14px;
        }

        /* 响应式调整 */
        @media (max-width: 768px) {
            .umkciz-nav-menu {
                display: none; /* 简化移动端，通常会配汉堡菜单 */
            }
            .umkciz-hero {
                padding: 64px 0;
                text-align: center;
            }
            .umkciz-hero-content {
                width: 100%;
            }
            .umkciz-search-box {
                margin: 0 auto;
            }
            .umkciz-hot-lexicon {
                padding: 32px;
                margin: 20px 12px;
            }
        }