* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: "PingFang SC", "Microsoft Yahei", sans-serif;
            scroll-behavior: smooth;
            transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
        }
        /* 浅色主题默认变量 */
        
         :root[data-theme="light"] {
            --black: #000000;
            --white: #ffffff;
            --bg-main: #ffffff;
            --bg-card: #ffffff;
            --text-main: #000000;
            --text-gray: #666666;
            --text-light-gray: #999999;
            --border-color: #e8e8e8;
            --gradient-light: linear-gradient(135deg, #f8f8f8 0%, #eaeaea 100%);
            --gradient-dark: linear-gradient(145deg, #1a1a1a 0%, #050505 100%);
            --shadow-soft: 0 4px 24px rgba(0, 0, 0, 0.06);
            --shadow-hover: 0 12px 32px rgba(0, 0, 0, 0.1);
            --nav-bg: rgba(255, 255, 255, 0.95);
        }
        /* 深色主题变量 */
        
         :root[data-theme="dark"] {
            --black: #ffffff;
            --white: #000000;
            --bg-main: #0a0a0a;
            --bg-card: #171717;
            --text-main: #ffffff;
            --text-gray: #aaaaaa;
            --text-light-gray: #777777;
            --border-color: #2a2a2a;
            --gradient-light: linear-gradient(135deg, #171717 0%, #0a0a0a 100%);
            --gradient-dark: linear-gradient(145deg, #242424 0%, #121212 100%);
            --shadow-soft: 0 4px 24px rgba(0, 0, 0, 0.2);
            --shadow-hover: 0 12px 32px rgba(0, 0, 0, 0.4);
            --nav-bg: rgba(20, 20, 20, 0.95);
        }
        
         :root {
            --radius-sm: 8px;
            --radius-md: 16px;
            --radius-lg: 30px;
            --transition: all 0.28s cubic-bezier(0.4, 0, 0.2, 1);
        }
        
        body {
            background: var(--bg-main);
            color: var(--text-main);
            line-height: 1.8;
            font-size: 15px;
        }
        
        .tag {
            display: inline-block;
            padding: 4px 12px;
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            font-size: 12px;
            color: var(--text-gray);
            margin-bottom: 12px;
            background: rgba(128, 128, 128, 0.1);
            backdrop-filter: blur(4px);
        }
        
        .divider {
            width: 60px;
            height: 2px;
            background: linear-gradient(90deg, var(--text-main) 0%, var(--text-gray) 100%);
            margin: 16px 0 24px;
        }
        /* 顶部导航栏 */
        
        header {
            width: 100%;
            height: 80px;
            background: var(--nav-bg);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border-color);
            position: fixed;
            top: 0;
            left: 0;
            z-index: 999;
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 0 40px;
            transition: var(--transition);
            box-shadow: var(--shadow-soft);
        }
        
        header:hover {
            box-shadow: var(--shadow-hover);
        }
        
        .logo {
            display: flex;
            align-items: center;
            height: 100%;
        }
        
        .logo img {
            height: 48px;
            width: auto;
            object-fit: contain;
            display: block;
            transition: var(--transition);
        }
        
        .logo img:hover {
            transform: scale(1.03);
        }
        
        .nav-list {
            display: flex;
            gap: 30px;
            align-items: center;
        }
        
        .nav-list a {
            text-decoration: none;
            color: var(--text-gray);
            font-size: 15px;
            font-weight: 500;
            transition: var(--transition);
            position: relative;
        }
        
        .nav-list a:hover {
            color: var(--text-main);
        }
        
        .nav-list a::after {
            content: '';
            position: absolute;
            bottom: -6px;
            left: 0;
            width: 0;
            height: 1.5px;
            background: linear-gradient(90deg, var(--text-main) 0%, var(--text-gray) 100%);
            transition: var(--transition);
        }
        
        .nav-list a:hover::after {
            width: 100%;
        }
        /* 导航栏右侧容器：按钮组 + 汉堡 */
        
        .header-right-group {
            display: flex;
            align-items: center;
            gap: 0;
        }
        /* 导航栏按钮组 —— 移动端始终显示 */
        
        .header-buttons {
            display: flex !important;
            gap: 16px;
            align-items: center;
        }
        
        .btn-experience {
            padding: 8px 20px;
            border-radius: var(--radius-lg);
            background: var(--text-main);
            color: var(--white);
            border: none;
            cursor: pointer;
            font-size: 14px;
            transition: var(--transition);
        }
        
        .btn-experience:hover {
            opacity: 0.85;
            transform: translateY(-2px);
        }
        
        .btn-theme {
            width: 40px;
            height: 40px;
            border-radius: 50%;
            border: 1px solid var(--border-color);
            background: transparent;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            transition: var(--transition);
            overflow: hidden;
        }
        
        .btn-theme img {
            width: 22px;
            height: 22px;
            object-fit: contain;
        }
        
        .btn-theme:hover {
            background: rgba(128, 128, 128, 0.15);
            transform: translateY(-2px);
        }
        /* 汉堡按钮 */
        
        .hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            cursor: pointer;
            /* 消除和按钮组之间的空隙 */
            margin-left: 12px;
        }
        
        .hamburger span {
            width: 24px;
            height: 2px;
            background: var(--text-main);
            transition: var(--transition);
        }
        /* 移动端侧边菜单 */
        
        .mobile-menu {
            position: fixed;
            top: 80px;
            right: 0;
            width: 280px;
            height: calc(100vh - 80px);
            background: var(--nav-bg);
            backdrop-filter: blur(12px);
            border-left: 1px solid var(--border-color);
            transform: translateX(100%);
            transition: var(--transition);
            z-index: 998;
            padding: 40px 30px;
        }
        
        .mobile-menu.active {
            transform: translateX(0);
        }
        
        .mobile-menu a {
            display: block;
            text-decoration: none;
            color: var(--text-main);
            font-size: 16px;
            padding: 12px 0;
            border-bottom: 1px solid var(--border-color);
            transition: var(--transition);
        }
        
        .mobile-menu a:hover {
            padding-left: 8px;
            color: var(--text-gray);
        }
        /* 首屏 */
        
        .banner {
            width: 100%;
            height: 100vh;
            padding-top: 80px;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            background: var(--gradient-light);
            position: relative;
            overflow: hidden;
            text-align: center;
        }
        
        .banner::before {
            content: '';
            position: absolute;
            width: 600px;
            height: 600px;
            border-radius: 50%;
            background: radial-gradient(circle, rgba(128, 128, 128, 0.08) 0%, transparent 70%);
            top: -200px;
            right: -200px;
        }
        
        .banner::after {
            content: '';
            position: absolute;
            width: 500px;
            height: 500px;
            border-radius: 50%;
            background: radial-gradient(circle, rgba(128, 128, 128, 0.05) 0%, transparent 70%);
            bottom: -150px;
            left: -150px;
        }
        
        .banner>* {
            position: relative;
            z-index: 2;
        }
        
        .banner-top-tag {
            margin-bottom: 20px;
        }
        
        .banner h1 {
            font-size: 86px;
            font-weight: 900;
            letter-spacing: 18px;
            margin-bottom: 24px;
            background: linear-gradient(135deg, var(--text-main) 0%, var(--text-gray) 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        
        .banner p {
            font-size: 20px;
            color: var(--text-gray);
            letter-spacing: 2px;
            margin-bottom: 48px;
        }
        
        .banner-btn {
            padding: 14px 46px;
            background: var(--text-main);
            color: var(--white);
            text-decoration: none;
            border-radius: var(--radius-lg);
            font-size: 16px;
            transition: var(--transition);
            border: 1px solid transparent;
            box-shadow: var(--shadow-soft);
        }
        
        .banner-btn:hover {
            opacity: 0.85;
            box-shadow: var(--shadow-hover);
            transform: translateY(-2px);
        }
        /* 通用容器 */
        
        .container {
            width: 90%;
            margin: 0 auto;
            padding: 100px 0;
        }
        
        .section-head {
            margin-bottom: 60px;
        }
        
        .section-head h2 {
            font-size: 36px;
            font-weight: 800;
            background: linear-gradient(135deg, var(--text-main) 0%, var(--text-gray) 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        
        .section-head p {
            color: var(--text-gray);
            max-width: 780px;
            font-size: 16px;
        }
        /* 网格布局 */
        
        .about-grid,
        .product-grid,
        .struct-grid,
        .join-grid,
        .tech-grid {
            display: grid;
            gap: 24px;
        }
        
        .about-grid {
            grid-template-columns: repeat(3, 1fr);
        }
        
        .product-grid {
            grid-template-columns: repeat(4, 1fr);
        }
        
        .struct-grid {
            grid-template-columns: repeat(2, 1fr);
        }
        
        .join-grid {
            grid-template-columns: repeat(3, 1fr);
        }
        
        .tech-grid {
            grid-template-columns: repeat(5, 1fr);
        }
        /* 卡片样式 */
        
        .card {
            border: 1px solid var(--border-color);
            border-radius: var(--radius-md);
            padding: 36px;
            transition: var(--transition);
            background: var(--bg-card);
            box-shadow: var(--shadow-soft);
        }
        
        .card:hover {
            transform: translateY(-6px);
            border-color: var(--text-main);
            box-shadow: var(--shadow-hover);
        }
        
        .card h3 {
            font-size: 20px;
            margin-bottom: 16px;
            font-weight: 700;
        }
        
        .card p {
            color: var(--text-gray);
            font-size: 15px;
            line-height: 1.8;
        }
        
        .product-card {
            text-align: center;
            padding: 32px 16px;
            border: 1px solid var(--border-color);
            border-radius: var(--radius-md);
            transition: var(--transition);
            background: var(--bg-card);
            box-shadow: var(--shadow-soft);
        }
        
        .product-card:hover {
            background: var(--gradient-light);
            border-color: var(--text-main);
            box-shadow: var(--shadow-hover);
            transform: translateY(-4px);
        }
        /* 技术生态区块 */
        
        .tech-wrap {
            background: var(--gradient-dark);
            color: #fff;
            padding: 60px 40px;
            border-radius: var(--radius-md);
            box-shadow: var(--shadow-soft);
            position: relative;
            overflow: hidden;
        }
        
        .tech-wrap::before {
            content: '';
            width: 300px;
            height: 300px;
            border-radius: 50%;
            background: radial-gradient(circle, rgba(255, 255, 255, 0.02) 0%, transparent 70%);
            position: absolute;
            top: -100px;
            right: -100px;
            z-index: 1;
        }
        
        .tech-wrap>* {
            position: relative;
            z-index: 2;
        }
        
        .tech-wrap .section-head h2 {
            background: linear-gradient(135deg, #fff 0%, #aaa 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        
        .tech-wrap .section-head p {
            color: #aaa;
        }
        
        .tech-wrap .tag {
            border-color: #333;
            color: #bbb;
            background: rgba(255, 255, 255, 0.05);
        }
        
        .tech-wrap .divider {
            background: linear-gradient(90deg, #fff 0%, #666 100%);
        }
        
        .tech-item {
            border: 1px solid #2a2a2a;
            padding: 20px 10px;
            text-align: center;
            border-radius: var(--radius-sm);
            font-size: 14px;
            color: #ccc;
            transition: var(--transition);
            background: rgba(255, 255, 255, 0.02);
        }
        
        .tech-item:hover {
            border-color: #fff;
            color: #fff;
            background: rgba(255, 255, 255, 0.06);
            transform: translateY(-2px);
        }
        
        .news-item {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 24px;
            border: 1px solid var(--border-color);
            border-radius: var(--radius-md);
            margin-bottom: 16px;
            transition: var(--transition);
            background: var(--bg-card);
            box-shadow: var(--shadow-soft);
        }
        
        .news-item:hover {
            border-color: var(--text-main);
            box-shadow: var(--shadow-hover);
            transform: translateX(4px);
        }
        /* 页脚样式 */
        
        footer {
            background: var(--gradient-dark);
            color: #fff;
            padding: 60px 0 30px;
            position: relative;
            overflow: hidden;
        }
        
        footer::before {
            content: '';
            width: 500px;
            height: 500px;
            border-radius: 50%;
            background: radial-gradient(circle, rgba(255, 255, 255, 0.02) 0%, transparent 70%);
            position: absolute;
            bottom: -200px;
            left: 50%;
            transform: translateX(-50%);
        }
        
        footer>* {
            position: relative;
            z-index: 2;
        }
        
        .footer-container {
            width: 90%;
            margin: 0 auto;
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 40px;
            margin-bottom: 40px;
        }
        
        .footer-col h3 {
            font-size: 18px;
            margin-bottom: 20px;
            color: #fff;
            border-left: 3px solid #666;
            padding-left: 12px;
        }
        
        .footer-col ul {
            list-style: none;
        }
        
        .footer-col ul li {
            margin-bottom: 12px;
        }
        
        .footer-col ul li a {
            color: #aaa;
            text-decoration: none;
            transition: var(--transition);
        }
        
        .footer-col ul li a:hover {
            color: #fff;
            padding-left: 6px;
        }
        
        .footer-bottom {
            text-align: center;
            padding-top: 30px;
            border-top: 1px solid #222;
        }
        
        .footer-bottom h2 {
            font-size: 28px;
            letter-spacing: 6px;
            margin-bottom: 16px;
            background: linear-gradient(135deg, #fff 0%, #999 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        
        .footer-desc {
            color: #aaa;
            margin: 12px 0;
        }
        
        .footer-copyright {
            color: #777;
            font-size: 13px;
            margin-top: 10px;
        }
        /* 移动端专属布局：按钮紧贴汉堡 */
        
        @media (max-width: 768px) {
            .nav-list {
                display: none;
            }
            .hamburger {
                display: flex;
            }
            header {
                padding: 0 16px;
            }
            /* 移动端按钮组和汉堡之间的距离 */
            .hamburger {
                margin-left: 12px;
            }
            .banner h1 {
                font-size: 40px;
                letter-spacing: 6px;
            }
            .banner p {
                font-size: 16px;
            }
            .section-head h2 {
                font-size: 28px;
            }
            .about-grid,
            .join-grid {
                grid-template-columns: 1fr;
            }
            .product-grid,
            .tech-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .news-item {
                flex-direction: column;
                align-items: flex-start;
                gap: 12px;
            }
            .footer-container {
                grid-template-columns: repeat(2, 1fr);
                gap: 30px;
            }
        }
        
        @media (max-width: 480px) {
            .product-grid,
            .tech-grid {
                grid-template-columns: 1fr;
            }
            .footer-container {
                grid-template-columns: 1fr;
            }
        }
        
        .back-to-top {
            position: fixed;
            right: 32px;
            bottom: 32px;
            width: 52px;
            height: 52px;
            border-radius: 50%;
            /* 背景自动跟随深浅主题，和全站卡片背景完全统一 */
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            box-shadow: var(--shadow-soft);
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            opacity: 0;
            visibility: hidden;
            transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
            z-index: 997;
            overflow: hidden;
        }
        
        .back-to-top.show {
            opacity: 1;
            visibility: visible;
        }
        
        .back-to-top:hover {
            transform: translateY(-4px) scale(1.05);
            border-color: var(--text-main);
            box-shadow: var(--shadow-hover);
        }
        
        .back-to-top img {
            /* 完美适配抠图箭头，居中不变形 */
            width: 24px;
            height: 24px;
            object-fit: contain;
            display: block;
            /* 箭头颜色自动跟随主题，抠图素材完美适配 */
            filter: var(--icon-filter, none);
        }