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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Microsoft YaHei', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
    overflow-x: hidden;
}

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

/* 头部导航 */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    transition: all 0.3s ease;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo img {
    height: 40px;
    width: auto;
}

.logo-text {
    font-size: 18px;
    font-weight: bold;
    color: #2c3e50;
}

.logo-text sup {
    font-size: 10px;
    color: #e74c3c;
}

.nav ul {
    display: flex;
    list-style: none;
    gap: 30px;
}

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

.nav a:hover {
    color: #3498db;
}

.nav a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #3498db;
    transition: width 0.3s ease;
}

.nav a:hover::after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background: #333;
    transition: 0.3s;
}

/* Banner区域 */
.banner {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 150px 0 100px;
    position: relative;
    overflow: hidden;
}

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

.banner h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.banner p {
    font-size: 1.2rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

.banner-btns {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
}

.btn-primary, .btn-secondary {
    padding: 12px 30px;
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
}

.btn-primary {
    background: #e74c3c;
    color: white;
}

.btn-primary:hover {
    background: #c0392b;
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: white;
    color: #333;
}

.banner-slider {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1s ease;
    background: rgba(0,0,0,0.3);
    display: flex;
    align-items: center;
    justify-content: center;
}

.slide.active {
    opacity: 1;
}

.slide-content {
    text-align: center;
    color: white;
}

.slide-content h3 {
    font-size: 2rem;
    margin-bottom: 10px;
}

/* 通用部分样式 */
.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 50px;
    color: #2c3e50;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background: #3498db;
}

/* 公司介绍 */
.about {
    padding: 80px 0;
    background: #f8f9fa;
}

.about-content {
    max-width: 1000px;
    margin: 0 auto;
}

.about-text p {
    margin-bottom: 20px;
    font-size: 1.1rem;
    line-height: 1.8;
}

.about-text h3 {
    color: #2c3e50;
    margin: 30px 0 20px;
    font-size: 1.5rem;
}

.business-departments {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.department {
    background: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    text-align: center;
    transition: transform 0.3s ease;
}

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

.department h4 {
    color: #3498db;
    margin-bottom: 10px;
}

/* 产品展示 */
.products {
    padding: 80px 0;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.product-card {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
}

.product-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.2);
}

.product-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.product-card:hover .product-image {
    transform: scale(1.05);
}

.product-info {
    padding: 20px;
}

.product-info h3 {
    color: #2c3e50;
    margin-bottom: 10px;
    font-size: 1.2rem;
}

.product-info p {
    color: #666;
    margin-bottom: 15px;
    font-size: 0.9rem;
    line-height: 1.5;
}

.product-price {
    color: #e74c3c;
    font-weight: bold;
    font-size: 1.1rem;
}

/* 应用领域 */
.applications {
    padding: 80px 0;
    background: #f8f9fa;
}

.applications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.application-item {
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    text-align: center;
    transition: transform 0.3s ease;
}

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

.application-item h3 {
    color: #3498db;
    margin-bottom: 15px;
    font-size: 1.3rem;
}

/* 常见问题 */
.faq {
    padding: 80px 0;
}

.faq-item {
    background: white;
    margin-bottom: 15px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    overflow: hidden;
}

.faq-question {
    padding: 20px;
    background: #f8f9fa;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: 600;
    transition: background 0.3s ease;
}

.faq-question:hover {
    background: #e9ecef;
}

.faq-question::after {
    content: '+';
    font-size: 1.5rem;
    transition: transform 0.3s ease;
}

.faq-item.active .faq-question::after {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 20px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
}

.faq-item.active .faq-answer {
    padding: 20px;
    max-height: 500px;
}

/* 友情链接 */
.friend-links {
    padding: 50px 0;
    background: #2c3e50;
    color: white;
}

.friend-links h3 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 1.8rem;
}

.links-grid {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 20px;
}

.links-grid a {
    color: white;
    text-decoration: none;
    padding: 10px 20px;
    border: 1px solid rgba(255,255,255,0.3);
    border-radius: 5px;
    transition: all 0.3s ease;
}

.links-grid a:hover {
    background: white;
    color: #2c3e50;
}

/* 联系方式 */
.contact {
    padding: 80px 0;
    background: #f8f9fa;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: start;
}

.contact-info h3 {
    color: #2c3e50;
    margin-bottom: 20px;
    font-size: 1.5rem;
}

.contact-item {
    margin-bottom: 15px;
    font-size: 1.1rem;
}

.contact-item strong {
    color: #3498db;
}

.qrcode {
    max-width: 150px;
    height: auto;
    margin-top: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
}

.city-links h3 {
    color: #2c3e50;
    margin-bottom: 20px;
    font-size: 1.5rem;
}

.cities-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 10px;
}

.cities-grid a {
    display: block;
    padding: 10px 15px;
    background: white;
    color: #333;
    text-decoration: none;
    text-align: center;
    border-radius: 5px;
    transition: all 0.3s ease;
    border: 1px solid #ddd;
}

.cities-grid a:hover {
    background: #3498db;
    color: white;
    transform: translateY(-2px);
}

/* 底部版权 */
.footer {
    background: #2c3e50;
    color: white;
    padding: 30px 0;
    text-align: center;
}

.footer-content p {
    margin-bottom: 10px;
}

.footer a {
    color: #3498db;
    text-decoration: none;
}

.footer a:hover {
    text-decoration: underline;
}

/* 图片模态框 */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.9);
    animation: fadeIn 0.3s;
}

.modal-content {
    margin: auto;
    display: block;
    max-width: 90%;
    max-height: 90%;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.close {
    position: absolute;
    top: 15px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    cursor: pointer;
    z-index: 2001;
}

.close:hover {
    color: #bbb;
}

#caption {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    color: white;
    text-align: center;
    width: 80%;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav ul {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 20px;
        box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    }

    .nav.active ul {
        display: flex;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .banner h1 {
        font-size: 2rem;
    }

    .banner p {
        font-size: 1rem;
    }

    .banner-btns {
        flex-direction: column;
        align-items: center;
    }

    .section-title {
        font-size: 2rem;
    }

    .contact-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .business-departments {
        grid-template-columns: 1fr;
    }

    .products-grid {
        grid-template-columns: 1fr;
    }

    .applications-grid {
        grid-template-columns: 1fr;
    }

    .cities-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .logo-text {
        font-size: 16px;
    }

    .banner {
        padding: 120px 0 80px;
    }

    .banner h1 {
        font-size: 1.8rem;
    }

    .section-title {
        font-size: 1.8rem;
    }

    .cities-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* 加载优化 */
img[loading="lazy"] {
    opacity: 0;
    transition: opacity 0.3s ease;
}

img[loading="lazy"].loaded {
    opacity: 1;
}

/* 性能优化 */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}