/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Microsoft YaHei', 'PingFang SC', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    overflow-x: hidden;
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 16px;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.3);
}

.btn-secondary {
    background: transparent;
    color: #667eea;
    border: 2px solid #667eea;
}

.btn-secondary:hover {
    background: #667eea;
    color: white;
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    z-index: 1000;
    transition: all 0.3s ease;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
    border-bottom: 1px solid rgba(102, 126, 234, 0.1);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: 0 4px 30px rgba(102, 126, 234, 0.15);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 15px;
    transition: transform 0.3s ease;
}

.nav-logo:hover {
    transform: scale(1.05);
}

.logo-img {
    width: 45px;
    height: 45px;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.2);
    transition: all 0.3s ease;
}

.logo-img:hover {
    transform: rotate(5deg);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.3);
}

.logo-text {
    font-size: 18px;
    font-weight: 700;
    color: #333;
}

.nav-menu {
    display: flex;
    gap: 30px;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover {
    color: #667eea;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #667eea;
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* 首页横幅 */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
}

.hero-bg-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: brightness(0.3) contrast(1.2);
    animation: heroZoom 20s ease-in-out infinite alternate;
}

@keyframes heroZoom {
    0% { transform: scale(1); }
    100% { transform: scale(1.1); }
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.8) 0%, rgba(118, 75, 162, 0.8) 100%);
    z-index: 2;
}

.hero-content {
    position: relative;
    z-index: 3;
    text-align: center;
    color: white;
    max-width: 1000px;
    padding: 0 20px;
    animation: fadeInUp 1s ease-out;
}

.hero-text {
    margin-bottom: 60px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 30px;
    line-height: 1.2;
}

.title-line {
    display: block;
    opacity: 0;
    animation: slideInUp 0.8s ease-out forwards;
}

.title-line:nth-child(1) {
    animation-delay: 0.2s;
}

.title-line:nth-child(2) {
    animation-delay: 0.4s;
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-subtitle {
    font-size: 1.4rem;
    margin-bottom: 25px;
    opacity: 0;
    animation: fadeIn 1s ease-out 0.6s forwards;
    font-weight: 300;
}

.hero-description {
    margin-bottom: 40px;
    opacity: 0;
    animation: fadeIn 1s ease-out 0.8s forwards;
}

.hero-description p {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.9);
    font-weight: 400;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    opacity: 0;
    animation: fadeIn 1s ease-out 1s forwards;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 30px;
    max-width: 600px;
    margin: 0 auto;
    opacity: 0;
    animation: fadeIn 1s ease-out 1.2s forwards;
}

.stat-item {
    text-align: center;
    padding: 20px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 15px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: all 0.3s ease;
}

.stat-item:hover {
    transform: translateY(-5px);
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.4);
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 800;
    color: #fff;
    margin-bottom: 10px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.stat-label {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.9);
    font-weight: 500;
}



/* 大屏幕优化 */
@media (min-width: 1400px) {
    .hero-content {
        max-width: 1600px; /* 大屏幕下进一步增加最大宽度 */
        padding: 100px 60px 80px; /* 大屏幕下调整内边距，避免内容被遮挡 */
    }
    
    .hero-text {
        max-width: 1000px; /* 大屏幕下增加文字区域宽度 */
        margin-top: 50px; /* 大屏幕下调整文字区域上方间距 */
        margin-bottom: 50px; /* 大屏幕下调整文字区域下方间距 */
    }
    
    .hero-title {
        font-size: 4rem; /* 大屏幕下适当增加标题大小，但避免过大 */
    }
    
    .hero-subtitle {
        font-size: 1.5rem; /* 大屏幕下适当增加副标题大小，但避免过大 */
    }
    
    .hero-description p {
        font-size: 1.1rem; /* 大屏幕下适当增加描述文字大小，但避免过大 */
    }
    
    .hero-stats {
        gap: 100px; /* 大屏幕下增加统计信息间距 */
        margin-top: 20px; /* 大屏幕下调整统计信息上方间距 */
    }
    
    .stat-number {
        font-size: 3rem; /* 大屏幕下适当增加统计数字大小，但避免过大 */
    }
}

/* 动画关键帧 */
@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}



/* 章节标题 */
.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: #333;
}

.section-subtitle {
    font-size: 1.1rem;
    color: #666;
    max-width: 600px;
    margin: 0 auto;
    margin-bottom: 30px;
}

.product-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px; /* 增加logo和文字之间的间距 */
    margin-bottom: 20px;
    flex-wrap: wrap; /* 在小屏幕上允许换行 */
}

.product-logo-img {
    width: 80px; /* 增加宽度以适配非正方形logo */
    height: 60px; /* 调整高度以保持比例 */
    border-radius: 12px;
    transition: transform 0.3s ease;
    object-fit: contain; /* 确保logo完整显示 */
    background: transparent; /* 透明背景 */
}

.product-logo-img:hover {
    transform: scale(1.1);
}

.product-logo-text {
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* 服务项目 */
.services {
    padding: 120px 0;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    position: relative;
    overflow: hidden;
}

.services::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="dots" width="20" height="20" patternUnits="userSpaceOnUse"><circle cx="10" cy="10" r="1" fill="%23667eea" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23dots)"/></svg>');
    opacity: 0.5;
}

.services .container {
    position: relative;
    z-index: 2;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
    margin-top: 60px;
}

.service-card {
    background: white;
    padding: 50px 35px;
    border-radius: 25px;
    text-align: center;
    transition: all 0.4s ease;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(102, 126, 234, 0.1);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.service-card:hover {
    transform: translateY(-15px);
    box-shadow: 0 25px 50px rgba(102, 126, 234, 0.2);
    border-color: rgba(102, 126, 234, 0.3);
}

.service-card:hover::before {
    opacity: 1;
}

.service-icon {
    width: 90px;
    height: 90px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 30px;
    position: relative;
    z-index: 2;
    transition: all 0.3s ease;
}

.service-card:hover .service-icon {
    transform: scale(1.1) rotate(5deg);
    box-shadow: 0 15px 30px rgba(102, 126, 234, 0.4);
}

.service-icon i {
    font-size: 40px;
    color: white;
    transition: transform 0.3s ease;
}

.service-card:hover .service-icon i {
    transform: scale(1.1);
}

.service-title {
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: 25px;
    color: #333;
    position: relative;
    z-index: 2;
}

.service-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 50px;
    height: 3px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 2px;
    transition: width 0.3s ease;
}

.service-card:hover .service-title::after {
    width: 80px;
}

.service-description {
    color: #666;
    margin-bottom: 30px;
    line-height: 1.7;
    position: relative;
    z-index: 2;
    font-size: 1rem;
}

.service-features {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    justify-content: center;
    position: relative;
    z-index: 2;
}

.feature-tag {
    background: linear-gradient(135deg, #f0f2ff 0%, #e8ecff 100%);
    color: #667eea;
    padding: 8px 18px;
    border-radius: 25px;
    font-size: 0.9rem;
    font-weight: 600;
    border: 1px solid rgba(102, 126, 234, 0.2);
    transition: all 0.3s ease;
}

.feature-tag:hover {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.3);
}

/* 产品展示 */
.products {
    padding: 100px 0;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
}

.product-section {
    margin-bottom: 80px;
}

.product-section:last-child {
    margin-bottom: 0;
}

.product-section-header {
    text-align: center;
    margin-bottom: 50px;
    padding: 40px 0;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.05) 0%, rgba(118, 75, 162, 0.05) 100%);
    border-radius: 20px;
    border: 1px solid rgba(102, 126, 234, 0.1);
}

.product-section-subtitle {
    font-size: 1.1rem;
    color: #666;
    margin-top: 15px;
    font-style: italic;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr); /* 强制四列布局 */
    gap: 20px; /* 减少间距以适应四列布局 */
    margin-top: 40px;
}

.product-card {
    background: #fff;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    transition: all 0.3s ease;
    position: relative;
    border: 1px solid rgba(102, 126, 234, 0.1);
    height: fit-content; /* 确保卡片高度适应内容 */
}

.product-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 25px 50px rgba(102, 126, 234, 0.2);
    border-color: rgba(102, 126, 234, 0.3);
}

.product-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.product-card:hover::before {
    transform: scaleX(1);
}

.product-image {
    width: 100%;
    height: 250px; /* 调整图片高度以适应四列布局 */
    object-fit: contain;
    background: #f8f9fa;
    border-radius: 20px 20px 0 0;
    transition: transform 0.3s ease;
    padding: 10px;
}

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

.product-title {
    padding: 25px 25px 15px;
    font-size: 1.3rem;
    font-weight: 600;
    color: #333;
    position: relative;
}

.product-title::after {
    content: '';
    position: absolute;
    bottom: 10px;
    left: 25px;
    width: 40px;
    height: 3px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 2px;
}

.product-description {
    padding: 0 25px 25px;
    color: #666;
    line-height: 1.6;
    font-size: 0.95rem;
}

/* 关于我们 */
.about {
    padding: 120px 0;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    position: relative;
    overflow: hidden;
}

.about::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="25" cy="25" r="1" fill="%23ffffff" opacity="0.1"/><circle cx="75" cy="75" r="1" fill="%23ffffff" opacity="0.1"/><circle cx="50" cy="10" r="0.5" fill="%23ffffff" opacity="0.1"/><circle cx="10" cy="60" r="0.5" fill="%23ffffff" opacity="0.1"/><circle cx="90" cy="40" r="0.5" fill="%23ffffff" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>');
    opacity: 0.3;
}

.about-content {
    display: block;
    max-width: 800px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
    text-align: center;
}

.about-text {
    animation: fadeInLeft 1s ease-out;
}

.about-text .section-title {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 30px;
    position: relative;
}

.about-text .section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    opacity: 0.8;
    border-radius: 2px;
}

.about-description {
    margin-bottom: 25px;
    color: #555;
    line-height: 1.8;
    font-size: 1.05rem;
    position: relative;
    padding-left: 20px;
}

.about-description::before {
    content: '✦';
    position: absolute;
    left: 0;
    top: 0;
    color: #667eea;
    font-size: 1.2rem;
}

.about-description:last-of-type {
    margin-bottom: 0;
}



/* 联系我们 */
.contact {
    padding: 120px 0;
    background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
    position: relative;
    overflow: hidden;
}

.contact::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="waves" width="100" height="20" patternUnits="userSpaceOnUse"><path d="M0,10 Q25,0 50,10 T100,10" stroke="%23667eea" stroke-width="1" fill="none" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23waves)"/></svg>');
    opacity: 0.3;
}

.contact .container {
    position: relative;
    z-index: 2;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    margin-top: 60px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 20px;
    padding: 30px;
    background: white;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(102, 126, 234, 0.1);
    transition: all 0.3s ease;
}

.contact-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(102, 126, 234, 0.15);
    border-color: rgba(102, 126, 234, 0.3);
}

.contact-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: all 0.3s ease;
}

.contact-item:hover .contact-icon {
    transform: scale(1.1) rotate(5deg);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.4);
}

.contact-icon i {
    font-size: 24px;
    color: white;
}

.contact-details h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: #333;
}

.contact-details p {
    color: #666;
    line-height: 1.6;
    font-size: 1rem;
}

.contact-form {
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(102, 126, 234, 0.1);
}

.form-group {
    margin-bottom: 25px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 15px 20px;
    border: 2px solid #e9ecef;
    border-radius: 15px;
    font-size: 1rem;
    transition: all 0.3s ease;
    background: #f8f9fa;
    color: #333;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
    background: white;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: #999;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.contact-form .btn {
    width: 100%;
    padding: 16px;
    font-size: 1.1rem;
    border-radius: 15px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
}

.contact-form .btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 30px rgba(102, 126, 234, 0.4);
}

/* 页脚 */
.footer {
    background: linear-gradient(135deg, #2c3e50 0%, #34495e 100%);
    color: white;
    padding: 60px 0 30px;
    position: relative;
    overflow: hidden;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="footer-dots" width="30" height="30" patternUnits="userSpaceOnUse"><circle cx="15" cy="15" r="1" fill="%23ffffff" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23footer-dots)"/></svg>');
    opacity: 0.3;
}

.footer .container {
    position: relative;
    z-index: 2;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 30px;
}

.footer-info {
    flex: 1;
    min-width: 300px;
}

.footer-info p {
    margin-bottom: 10px;
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.95rem;
}

.beian-link {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: color 0.3s ease;
}

.beian-link:hover {
    color: #667eea;
}

.footer-social {
    display: flex;
    gap: 20px;
}

.social-link {
    width: 50px;
    height: 50px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.social-link:hover {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.4);
    border-color: transparent;
}

.social-link i {
    font-size: 20px;
}

/* 返回顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    transition: all 0.3s ease;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.3);
    z-index: 1000;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(102, 126, 234, 0.4);
}

.back-to-top i {
    transition: transform 0.3s ease;
}

.back-to-top:hover i {
    transform: translateY(-2px);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 100%;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 20px;
        box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
        transform: translateY(-100%);
        transition: transform 0.3s ease;
    }
    
    .nav-menu.active {
        transform: translateY(0);
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero-content {
        flex-direction: column;
        text-align: center;
        gap: 40px;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .about-content,
    .contact-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .services-grid {
        grid-template-columns: 1fr;
    }
    
    .products-grid {
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .container {
        padding: 0 15px;
    }
    
    .service-card,
    .product-card {
        padding: 20px;
    }
}

/* 动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 滚动动画 */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 响应式优化 */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .hero-stats {
        grid-template-columns: repeat(3, 1fr);
        gap: 20px;
    }
    
    .stat-item {
        padding: 15px;
    }
    
    .stat-number {
        font-size: 2rem;
    }
    
    .services-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .products-grid {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 25px;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
    
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: rgba(255, 255, 255, 0.98);
        backdrop-filter: blur(15px);
        flex-direction: column;
        justify-content: flex-start;
        align-items: center;
        padding-top: 50px;
        transition: left 0.3s ease;
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-link {
        margin: 15px 0;
        font-size: 1.2rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.1rem;
    }
    
    .hero-description p {
        font-size: 1rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .service-card {
        padding: 30px 25px;
    }
    
    .product-card {
        border-radius: 15px;
    }
    
    .contact-form {
        padding: 30px 25px;
    }
    
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 50px;
        height: 50px;
        font-size: 18px;
    }
}

/* 加载动画 */
.loading {
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.6s ease;
}

.loading.loaded {
    opacity: 1;
    transform: translateY(0);
}

/* 悬停效果增强 */
.hover-lift {
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.hover-lift:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(102, 126, 234, 0.2);
}

/* 渐变文字效果 */
.gradient-text {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* 卡片悬停效果 */
.card-hover {
    transition: all 0.3s ease;
}

.card-hover:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 40px rgba(102, 126, 234, 0.15);
}