:root {
            --primary-color: #1d1d1f;
            --secondary-color: #86868b;
            --accent-color: #0071e3;
            --bg-color: #f5f5f7;
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: -apple-system, BlinkMacSystemFont, 
                'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell,
                'Open Sans', 'Helvetica Neue', sans-serif;
        }

        body {
            background-color: var(--bg-color);
            color: var(--primary-color);
            -webkit-font-smoothing: antialiased;
            overflow-x: hidden;
        }

        /* 导航容器 */
        .nav-container {
            position: fixed;
            top: 0;
            width: 100%;
            background: rgba(255, 255, 255, 0.8);
            -webkit-backdrop-filter: blur(20px); /* Safari 支持 */
            backdrop-filter: blur(20px); /* 添加模糊效果 */
            z-index: 1000;
            border-bottom: 1px solid rgba(0, 0, 0, 0.1);
        	
        }
        
        /* 导航主体 */
        .nav-wrapper {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        
        /* 主导航栏（高度由全站 hzbgs-layout / nav-override 接管，勿写死 60px 以免裁切两行标题） */
        .main-nav {
            display: flex;
            justify-content: flex-start;
            align-items: center;
            min-height: 60px;
            height: auto;
        }
        
        .logo {
            font-size: 24px;
            font-weight: 600;
            color: #000;
            text-decoration: none;
        }
        
        /* 导航菜单 */
        .nav-menu {
            display: flex;
            list-style: none;
            height: 100%;
        }
        
        .nav-item {
            position: relative;
            padding: 0 20px;
            height: 100%;
            display: flex;
            align-items: center;
        }
        
        .nav-link {
            text-decoration: none;
            color: #666;
            font-size: 14px;
            transition: color 0.3s;
            position: relative;
        }
        
        .nav-link:hover {
            color: #000;
        }
        
        /* 横向下拉菜单 */
        .dropdown-horizontal {
            position: absolute;
            top: 100%;
            left: 0;
            width: 200vw;
            margin-left: -100vw;
            left: 50%;
            background: rgba(255,255,255,0.92);
            -webkit-backdrop-filter: blur(30px); /* Safari 支持 */
            backdrop-filter: blur(30px); /* 添加模糊效果 */
            display: none;
            padding: 40px 0;
            box-shadow: 0 20px 30px rgba(0,0,0,0.1);
            border-top: 1px solid rgba(0,0,0,0.1);
        }
        
        .dropdown-content {
            max-width: 1200px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 40px;
            padding: 0 20px;
        }
        
        .menu-section h3 {
            font-size: 12px;
            color: #666;
            margin-bottom: 15px;
            font-weight: 500;
            text-transform: uppercase;
        }
        
        .menu-section ul {
            list-style: none;
        }
        
        .menu-section li {
            margin-bottom: 12px;
        }
        
        .menu-section a {
            color: #000;
            text-decoration: none;
            font-size: 16px;
            transition: opacity 0.3s;
        }
        
        .menu-section a:hover {
            opacity: 0.7;
        }
        
        /* 交互效果 */
        .nav-item:hover .dropdown-horizontal {
            display: block;
            animation: menuSlide 0.3s cubic-bezier(0.23, 1, 0.32, 1);
        }
        
        @keyframes menuSlide {
            from {
                opacity: 0;
                transform: translateY(-10px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        /* 主内容：首屏仅标题与导语（无大图） */
        .hero-section {
            min-height: 0;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            text-align: center;
            padding: 96px 20px 48px;
            max-width: 920px;
            margin: 0 auto;
            opacity: 0;
            transform: translateY(80px);
            transition: all 1s cubic-bezier(0.4, 0, 0.2, 1);
        }

        .hero-section.active {
            opacity: 1;
            transform: translateY(0);
        }

        .hero-section h1 {
            font-size: clamp(32px, 5vw, 56px);
            font-weight: 600;
            margin: 0 0 20px;
            line-height: 1.12;
            color: var(--primary-color, #1d1d1f);
        }

        .hero-text {
            font-size: clamp(17px, 2.2vw, 22px);
            color: var(--secondary-color);
            max-width: 52ch;
            margin: 0 auto;
            line-height: 1.55;
        }

        /* 研究院介绍模块 */
        .about-section {
            padding: 72px 20px 100px;
            max-width: 980px;
            margin: 0 auto;
            opacity: 0;
            transform: translateY(80px);
            transition: all 1s cubic-bezier(0.4, 0, 0.2, 1);
        }

        .about-section.active {
            opacity: 1;
            transform: translateY(0);
        }

        .section-title {
            font-size: 40px;
            font-weight: 600;
            margin-bottom: 40px;
            text-align: center;
        }

        .about-grid {
            display: grid;
            grid-template-columns: repeat(1, 1fr);
            /* gap: 60px; */
            align-items: center;
        }

        .about-image {
            border-radius: 18px;
            overflow: hidden;
            box-shadow: 0 25px 50px -12px rgba(0,0,0,0.1);
        }

        .about-text {
            font-size: 18px;
            color: var(--secondary-color);
            line-height: 1.5;
            max-width: 920px;
            margin: 0 auto;
        }

        .about-text p {
            text-indent: 2em;
            text-align: justify;
            line-height: 1.5;
            margin-bottom: 1.1em;
        }

        .about-text p:last-child {
            margin-bottom: 0;
        }

        .highlight {
            color: var(--primary-color);
            font-weight: 500;
        }

        /* 研究方向模块 */
        .research-section {
            padding: 120px 20px;
            background: white;
            margin: 120px 0;
            opacity: 0;
            transform: translateY(80px);
            transition: all 1s cubic-bezier(0.4, 0, 0.2, 1);
        }

        /* 发展历程模块 */
        .timeline-section {
            padding: 80px 20px;
            background: var(--bg-color);
            margin: 80px 0;
            opacity: 0;
            transform: translateY(80px);
            transition: opacity 1s ease, transform 1s ease;
        }

        .timeline-section.active {
            opacity: 1;
            transform: translateY(0);
        }

        .timeline-container {
            max-width: 1200px;
            margin: 0 auto;
            display: flex;
            justify-content: space-between;
            gap: 40px;
        }

        .timeline-item {
            flex: 1;
            padding: 30px;
            background: white;
            border-radius: 12px;
            box-shadow: 0 5px 15px rgba(0,0,0,0.05);
            transition: transform 0.3s ease;
            height: 300px; /* 统一高度 */
        }

        .timeline-item:hover {
            transform: translateY(-5px);
        }

        .timeline-date {
            font-size: 16px; /* 缩小字体 */
            color: var(--accent-color);
            margin-bottom: 12px;
            font-weight: 600;
        }

        .timeline-title {
            font-size: 20px;
            font-weight: 700;
            margin-bottom: 10px;
            /* white-space: nowrap; */
            white-space: normal;
            word-break: break-all;
            line-height: 1.3;
            text-align: left;
        }

        .timeline-description {
            font-size: 14px; /* 缩小字体 */
            color: var(--secondary-color);
            line-height: 1.5;
        }

        @media (max-width: 768px) {
            .timeline-container {
                flex-direction: column;
            }
        }

        .timeline-container {
            display: flex;

min-width: 1200px;
            padding: 80px 0 40px;
            position: relative;
            gap: 20px;
            cursor: grab;
            user-select: none;
            scroll-snap-type: x mandatory;
        }

        .timeline-item {
            flex: 0 0 300px;
            scroll-snap-align: start;
            position: relative;
            height: 320px; /* 降低整体高度 */
        }

        .timeline-content {
            margin-top: 60px;
            background: white;
            border-radius: 12px;
            padding: 20px; /* 减少内边距 */
            box-shadow: 0 5px 15px rgba(0,0,0,0.05);
            opacity: 0;
            transform: translateY(20px);
            transition: all 0.6s ease;
            height: 240px; /* 降低内容高度 */
        }

        .timeline-date {
            font-size: 18px; /* 缩小日期字体 */
            color: var(--accent-color);
            margin-bottom: 12px;
            font-weight: 600;
        }

        .timeline-title {
            font-size: 24px; /* 缩小标题字体 */
            font-weight: 600;
            margin-bottom: 12px;
            line-height: 1.2;
            white-space: nowrap; /* 保证标题一行显示 */
        }

        .timeline-description {
            font-size: 16px; /* 缩小描述字体 */
            color: var(--secondary-color);
            line-height: 1.4; /* 调整行高 */
            margin-bottom: 8px; /* 减少段落间距 */
        }

        .timeline-content.active {
            opacity: 1;
            transform: translateY(0);
        }

        .timeline-container::before {
            content: '';
            position: absolute;
            left: 0;
            right: 0;
            top: 60px;
            height: 2px;
            background: linear-gradient(to right, var(--accent-color), rgba(0,113,227,0.3));
            transform: translateY(-50%);
            z-index: 1;
        }

        .timeline-item::after {
            content: '';
            position: absolute;
            top: 60px;
            left: 50%;
            width: 16px;
            height: 16px;
            background: var(--accent-color);
            border-radius: 50%;
            transform: translate(-50%, -50%);
            z-index: 2;
            box-shadow: 0 0 0 4px rgba(0,113,227,0.2);
            transition: all 0.3s ease;
        }

        .timeline-item:hover::after {
            transform: translate(-50%, -50%) scale(1.2);
            box-shadow: 0 0 0 8px rgba(0,113,227,0.3);
        }

        .timeline-item {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 60px;
            margin-bottom: 120px;
            align-items: center;
        }

        .timeline-item:last-child {
            margin-bottom: 0;
        }

        .timeline-content {
            padding: 40px;
        }

        .timeline-date {
            font-size: 24px;
            color: var(--accent-color);
            margin-bottom: 20px;
            font-weight: 600;
        }

        .timeline-title {
            font-size: 36px;
            font-weight: 600;
            margin-bottom: 20px;
            line-height: 1.2;
            white-space: nowrap; /* 保证标题一行显示 */
        }

        .timeline-description {
            font-size: 19px;
            color: var(--secondary-color);
            line-height: 1.5;
        }

        .timeline-image {
            border-radius: 18px;
            overflow: hidden;
            box-shadow: 0 25px 50px -12px rgba(0,0,0,0.1);
            transition: transform 0.3s ease;
        }

        .timeline-image:hover {
            transform: scale(1.02);
        }

        .timeline-image img {
            width: 100%;
            height: auto;
            display: block;
        }

        @media (max-width: 768px) {
            .timeline-item {
                grid-template-columns: 1fr;
                gap: 40px;
            }

            .timeline-content {
                order: 2;
            }

            .timeline-image {
                order: 1;
            }
        }

        /* 响应式设计 */
        @media (max-width: 768px) {
            .hero-section {
                padding: 72px 16px 32px;
            }

            .hero-section h1 {
                font-size: clamp(26px, 7vw, 36px);
            }

            .hero-text {
                font-size: 16px;
                line-height: 1.5;
            }

            .about-grid,
            .research-grid {
                grid-template-columns: 1fr;
            }

            .about-text {
                font-size: 15px;
            }

            .about-text p {
                font-size: 15px;
                line-height: 1.5;
                margin-bottom: 1em;
            }

            .section-title {
                font-size: 24px;
            }

            .contact-title {
                font-size: 24px;
            }

            .contact-details {
                font-size: 15px;
            }

            .timeline-section .timeline-date,
            .timeline-section .timeline-title,
            .timeline-section .timeline-description {
                font-size: 14px;
            }
        }
		
		/* 页脚 */
		footer {
		    background: #1d1d1f;
		    color: #f5f5f7;
		    padding: 40px 20px;
		    text-align: center;
			position: relative;
			bottom: 0px;
		}
		
		footer a {
		    color: #f5f5f7;
		    text-decoration: none;
		    margin: 0 10px;
		}
		
		footer a:hover {
		    text-decoration: underline;
		}

        /* 联系我们模块 */
        .contact-section {
            padding: 120px 20px;
            background: white;
            margin: 120px 0;
            opacity: 0;
            transform: translateY(80px);
            transition: all 1s cubic-bezier(0.4, 0, 0.2, 1);
        }

        .contact-section.active {
            opacity: 1;
            transform: translateY(0);
        }

        .contact-container {
            max-width: 980px;
            margin: 0 auto;
        }

        .contact-info {
            text-align: center;
            margin-bottom: 60px;
        }

        .contact-title {
            font-size: 48px;
            font-weight: 600;
            margin-bottom: 40px;
            line-height: 1.2;
        }

        .contact-details {
            font-size: 21px;
            color: var(--secondary-color);
            line-height: 1.8;
        }

        .contact-details p {
            margin-bottom: 15px;
        }

        .contact-details strong {
            color: var(--primary-color);
            font-weight: 600;
        }

        .map-container {
            border-radius: 18px;
            overflow: hidden;
            box-shadow: 0 25px 50px -12px rgba(0,0,0,0.1);
            transition: transform 0.3s ease;
        }

        .map-container:hover {
            transform: scale(1.02);
        }

        .map-container img {
            width: 100%;
            height: auto;
            display: block;
        }

        @media (max-width: 768px) {
            .contact-title {
                font-size: 36px;
            }

            .contact-details {
                font-size: 18px;
            }
        }

        /* 产品 */
        .project-section {
            max-width: 1200px;
            margin: 0 auto;
            padding: 30px 20px;
            text-align: center;
            position: relative;
            top: 900px;
            display: flex;
            flex-direction: column;
            justify-content: center;
            min-height: 100vh;
        }
        
        .project-section h2 {
            font-size: 32px;
            font-weight: 600;
            margin-bottom: 40px;
        }
        
        .project-grid {
            display: flex;
            justify-content: center;
            align-items: center;
            gap: 30px;
            max-width: 800px;
            margin: 0 auto;
        }

        /* 横向时间轴样式 */
.timeline-horizontal {
    position: relative;
    width: 100%;
    overflow-x: auto;
    overflow-y: visible;
    padding: 60px 0 40px 0;
    margin-bottom: 40px;
    min-width: 0;
    display: flex;
    flex-direction: column;
    align-items: center; /* 居中整个时间轴内容 */
}
.timeline-track {
    position: absolute;
    top: 24px;
    left: 50%;
    height: 4px;
    width: 100vw;
    background: var(--accent-color);
    z-index: 1;
    transform: translate(-50%, 0); /* 横向居中并占满全屏 */
}
@media (max-width: 900px) {
    .timeline-track {
        left: -20px; /* 向左偏移以显示开头 */
        width: calc(100% + 1190px); /* 增加更多宽度确保超出最后一个点 */
        transform: none;
    }
    .timeline-horizontal {
        overflow-x: hidden; /* 防止出现水平滚动条 */
    }
}
.timeline-cards {
    display: flex;
    gap: 40px;
    position: relative;
    z-index: 2;
    padding: 0;
    align-items: flex-start;
    justify-content: center; /* 居中显示所有卡片 */
    width: auto;
    box-sizing: border-box;
    margin: 0 auto;
    /* 居中显示所有卡片，且不强制左右留白 */
}
.timeline-card {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    min-width: 220px;
    max-width: 260px;
    background: none;
    box-shadow: none;
    padding: 0;
    flex-shrink: 0;
}
.timeline-dot {
    width: 18px;
    height: 18px;
    background: var(--accent-color);
    border-radius: 50%;
    border: 3px solid #fff;
    box-shadow: 0 0 0 4px rgba(0,113,227,0.15);
    position: absolute;
    top: -43px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 3;
}
.timeline-card-content {
    margin-top: 10px;
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 4px 24px rgba(0,0,0,0.08);
    padding: 32px 24px 24px 24px;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    min-width: 0;
    max-width: 100%;
}
.timeline-date {
    font-size: 16px;
    color: var(--accent-color);
    font-weight: 600;
    margin-bottom: 10px;
    text-align: left;
    width: 100%;
}
.timeline-title {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 10px;
    white-space: normal;
    word-break: break-all;
    line-height: 1.3;
    text-align: left;
}
.timeline-description {
    font-size: 15px;
    color: var(--secondary-color);
    line-height: 1.6;
    text-align: left;
    width: 100%;
}

/* 移动端样式 */
@media (max-width: 900px) {
    .timeline-horizontal {
        min-width: 0;
        width: 100vw;
        padding: 60px 0 40px 0;
        overflow-x: auto;
    }
    .timeline-cards {
        gap: 16px;
        padding: 0 8px;
        justify-content: flex-start;
    }
    .timeline-card {
        min-width: 85vw;
        max-width: 90vw;
        box-sizing: border-box;
        align-items: flex-start;
    }
    .timeline-card-content {
        min-width: 0;
        max-width: 100%;
        padding: 16px 8px 12px 8px;
        display: flex;
        flex-direction: column;
        align-items: flex-start;
    }
    .timeline-date {
        font-size: 15px;
        margin-bottom: 6px;
        text-align: left;
        width: 100%;
    }
    .timeline-title {
        font-size: 17px;
        margin-bottom: 8px;
        text-align: left;
        line-height: 1.3;
        word-break: break-all;
        white-space: normal;
    }
    .timeline-description {
        font-size: 14px;
        line-height: 1.5;
        text-align: left;
        width: 100%;
    }
}

/* PC端时间轴卡片样式（900px以上） */
@media (min-width: 901px) {
    .timeline-horizontal {
        min-width: 0;
        width: 100%;
        max-width: 1200px;
        margin-left: auto;
        margin-right: auto;
        padding: 60px 0 40px 0;
        overflow-x: visible;
        display: flex;
        flex-direction: column;
        align-items: center;
    }
    .timeline-cards {
        gap: 48px;
        padding: 0;
        justify-content: center;
        width: auto;
        margin: 0 auto;
    }
    .timeline-card {
        min-width: 260px;
        max-width: 320px;
        box-sizing: border-box;
        flex-shrink: 0;
    }
    .timeline-card-content {
        min-width: 0;
        max-width: 100%;
        padding: 32px 24px 24px 24px;
        display: flex;
        flex-direction: column;
        align-items: flex-start;
    }
    .timeline-date {
        font-size: 18px;
        margin-bottom: 12px;
        text-align: left;
        width: 100%;
    }
    .timeline-title {
        font-size: 24px;
        margin-bottom: 12px;
        text-align: left;
        line-height: 1.2;
        word-break: break-all;
        white-space: normal;
    }
    .timeline-description {
        font-size: 16px;
        line-height: 1.4;
        text-align: left;
        width: 100%;
    }
}

        /* 移动端样式 */
        @media (min-width: 769px) {
            /* PC端时隐藏移动端导航 */
            .mobile-header,
            .mobile-menu {
                display: none !important;
            }
            
            /* PC端时显示主导航 */
            .nav-container {
                display: block;
            }
        }

        @media (max-width: 768px) {
            /* 移动端时隐藏PC导航 */
            .nav-container {
                display: none !important;
            }
            
            /* 移动端时显示移动导航 */
            .mobile-header {
                display: flex !important;
            }
        }
        @media (max-width: 600px) {
            .nav-container {
                display: none; /* 隐藏桌面导航 */
            }

            .mobile-header {
                display: flex;
                justify-content: space-between;
                align-items: center;
                padding: 10px 20px;
                background: rgba(255, 255, 255, 0.9);
                border-bottom: 1px solid rgba(0, 0, 0, 0.1);
                position: relative;
                z-index: 1001;
            }

            /* 移动端菜单按钮和菜单样式 */
        @media (max-width: 768px) {
            .main-nav, .nav-menu, .nav-login {
                display: none !important;
            }
            .mobile-header {
                display: flex;
                align-items: center;
                justify-content: space-between;
                height: 60px;
                padding: 0 16px;
                background: rgba(255,255,255,0.95);
                position: fixed;
                top: 0;
                left: 0;
                width: 104vw;
                z-index: 1200;
                border-bottom: 1px solid #eee;
            }
            .mobile-logo {
                font-size: 16px;
                font-weight: 600;
                color: #222;
                text-decoration: none;
                flex: 1;
                white-space: nowrap;
                overflow: hidden;
                text-overflow: ellipsis;
            }
            .mobile-logo-en {
                font-size: 8px !important;
                color: #444;
                margin-top: 2px;
                letter-spacing: 1px;
                font-weight: 400;
                white-space: nowrap;
                line-height: 1;
                text-overflow: ellipsis;
                overflow: hidden;
                max-width: 100vw;
            }
            .mobile-menu-btn {
                background: none;
                border: none;
                font-size: 28px;
                color: #222;
                cursor: pointer;
                padding: 8px;
                margin-left: 90px;
            }
            .mobile-menu {
                display: none;
                position: fixed;
                top: 0;
                left: 0;
                width: 100vw;
                height: 100vh;
                background: #222;
                color: #fff;
                z-index: 2000;
                flex-direction: column;
                padding-top: 60px;
                transition: transform 0.3s cubic-bezier(.4,0,.2,1);
                overflow-y: auto; /* 允许菜单内容滚动 */
                -webkit-overflow-scrolling: touch; /* iOS 惯性滚动 */
            }
            .mobile-menu.active {
                display: flex;
            }
            body.mobile-menu-open {
                overflow: hidden;
                position: fixed;
                width: 100vw;
            }
            .mobile-menu-close {
                position: absolute;
                top: 16px;
                right: 20px;
                background: none;
                border: none;
                color: #fff;
                font-size: 28px;
                cursor: pointer;
                z-index: 2100;
            }
            .mobile-menu-list {
                list-style: none;
                padding: 0;
                margin: 0;
                width: 100%;
            }
            .mobile-menu-list li {
                border-bottom: 1px solid rgba(255,255,255,0.08);
            }
            .mobile-menu-link {
                display: block;
                color: #fff;
                text-decoration: none;
                font-size: 18px;
                padding: 18px 28px;
                width: 100%;
                transition: background 0.2s;
            }
            .mobile-menu-link:hover {
                background: rgba(255,255,255,0.08);
            }
            .mobile-menu-dropdown {
                background: #222;
                padding-left: 32px;
            }
            .mobile-menu-dropdown a {
                color: #fff;
                font-size: 16px;
                display: block;
                padding: 12px 0;
                text-decoration: none;
            }
            .mobile-menu-dropdown a:hover {
                text-decoration: underline;
            }
            body.mobile-menu-open {
                overflow: hidden;
            }
            .carousel-container {
                margin-top: 60px !important;
            }
            .carousel-caption {
                position: absolute;
                left: 0;
                right: 0;
                bottom: 0;
                width: 100%;
                max-width: 100%;
                padding: 0.7rem 0.7rem 0.9rem 0.7rem;
                background: rgba(0,0,0,0.32);
                text-align: left;
                color: #fff;
                animation: fadeIn 1.5s ease-in-out;
            }
            .carousel-caption h2 {
                font-size: 1.15rem;
                margin-bottom: 0.5rem;
                font-weight: 700;
                color: #fff;
                text-shadow: 0 2px 6px rgba(0,0,0,0.25);
                line-height: 1.3;
            }
            .carousel-caption p {
                font-size: 0.92rem;
                margin-bottom: 0.7rem;
                line-height: 1.5;
                color: #fff;
                text-shadow: 0 1px 3px rgba(0,0,0,0.18);
            }
            .read-more {
                padding: 7px 14px;
                font-size: 0.92rem;
            }
        }