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

:root {
    --primary-color: #3498db;
    --secondary-color: #2ecc71;
    --tertiary-color: #e74c3c;
    --dark-color: #2c3e50;
    --light-color: #ecf0f1;
    --accent-color1: #f39c12;
    --accent-color2: #9b59b6;
    --accent-color3: #1abc9c;
    --text-color: #333;
    --text-light: #7f8c8d;
    --white: #fff;
    --section-padding: 80px 0;
    --transition: all 0.3s ease;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    overflow-x: hidden;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 4px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}

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

.btn-primary:hover {
    background-color: #2980b9;
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: var(--white);
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.btn-tertiary {
    color: var(--primary-color);
    font-weight: 500;
    padding: 8px 0;
}

.btn-tertiary:hover {
    color: #2980b9;
}

.section-padding {
    padding: var(--section-padding);
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 36px;
    margin-bottom: 15px;
    color: var(--dark-color);
}

.section-header .line {
    width: 80px;
    height: 3px;
    background-color: var(--primary-color);
    margin: 0 auto 20px;
}

.section-header p {
    font-size: 16px;
    color: var(--text-light);
    max-width: 700px;
    margin: 0 auto;
}

/* 导航栏样式 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.95);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    transition: var(--transition);
}

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

.logo a {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
    display: flex;
    align-items: center;
}

.logo i {
    margin-right: 10px;
    font-size: 28px;
}

.nav-links {
    display: flex;
}

.nav-links li {
    margin-left: 30px;
}

.nav-links a {
    font-weight: 500;
    color: var(--dark-color);
    transition: var(--transition);
    position: relative;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition);
}

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

.mobile-nav-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    color: var(--dark-color);
    cursor: pointer;
}

/* 英雄区域样式 */
.hero {
    height: 100vh;
    background: linear-gradient(135deg, rgba(52, 152, 219, 0.8), rgba(46, 204, 113, 0.8)), url('https://picsum.photos/id/1/1920/1080') center/cover no-repeat fixed;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--white);
    padding: 0 20px;
}

.hero-content h1 {
    font-size: 50px;
    margin-bottom: 20px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.hero-content p {
    font-size: 20px;
    margin-bottom: 30px;
    max-width: 800px;
    text-shadow: 0 1px 5px rgba(0, 0, 0, 0.3);
}

.hero-content .btn {
    margin: 0 10px;
}

/* 关于我们样式 */
.about-content {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 40px;
}

.about-img {
    flex: 1;
    min-width: 300px;
}

.about-text {
    flex: 1;
    min-width: 300px;
}

.about-text h3 {
    font-size: 24px;
    margin-bottom: 15px;
    color: var(--dark-color);
}

.about-text p {
    margin-bottom: 20px;
    color: var(--text-light);
}

.about-features {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    margin-top: 30px;
}

.feature-item {
    flex: 1;
    min-width: 150px;
    text-align: center;
    padding: 20px;
    background-color: var(--light-color);
    border-radius: 4px;
    transition: var(--transition);
}

.feature-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.feature-item i {
    font-size: 36px;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.feature-item h4 {
    font-size: 18px;
    margin-bottom: 10px;
    color: var(--dark-color);
}

/* 核心优势样式 */
.advantages {
    color: var(--white);
}

.bg-gradient {
    background: linear-gradient(135deg, var(--accent-color2), var(--primary-color));
}

.advantages-content {
    display: flex;
    flex-wrap: wrap;
    gap: 30px;
}

.advantage-item {
    flex: 1;
    min-width: 250px;
    text-align: center;
    padding: 30px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 4px;
    transition: var(--transition);
}

.advantage-item:hover {
    transform: translateY(-10px);
    background-color: rgba(255, 255, 255, 0.2);
}

.advantage-icon {
    width: 80px;
    height: 80px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
}

.advantage-icon i {
    font-size: 36px;
    color: var(--white);
}

.advantage-item h3 {
    font-size: 22px;
    margin-bottom: 15px;
}

/* 产品介绍样式 */
.products-content {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.product-item {
    background-color: var(--white);
    border-radius: 4px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: var(--transition);
}

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

.product-img {
    height: 200px;
    overflow: hidden;
}

.product-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

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

.product-info {
    padding: 20px;
}

.product-info h3 {
    font-size: 20px;
    margin-bottom: 10px;
    color: var(--dark-color);
}

.product-info p {
    margin-bottom: 15px;
    color: var(--text-light);
}

/* 新闻资讯样式 */
.bg-light {
    background-color: var(--light-color);
}

.news-content {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.news-item {
    background-color: var(--white);
    border-radius: 4px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: var(--transition);
}

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

.news-img {
    height: 200px;
    overflow: hidden;
}

.news-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.news-item:hover .news-img img {
    transform: scale(1.1);
}

.news-info {
    padding: 20px;
}

.news-date {
    font-size: 14px;
    color: var(--primary-color);
    margin-bottom: 10px;
    display: flex;
    align-items: center;
}

.news-date i {
    margin-right: 5px;
}

.news-info h3 {
    font-size: 18px;
    margin-bottom: 10px;
    color: var(--dark-color);
}

.news-info p {
    margin-bottom: 15px;
    color: var(--text-light);
}

.read-more {
    color: var(--primary-color);
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    transition: var(--transition);
}

.read-more i {
    margin-left: 5px;
    transition: var(--transition);
}

.read-more:hover {
    color: #2980b9;
}

.read-more:hover i {
    margin-left: 10px;
}

/* 联系我们样式 */
.contact-content {
    display: flex;
    flex-wrap: wrap;
    gap: 40px;
}

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

.contact-form {
    flex: 1;
    min-width: 300px;
}

.contact-item {
    display: flex;
    margin-bottom: 30px;
}

.contact-item i {
    font-size: 24px;
    color: var(--primary-color);
    margin-right: 20px;
    width: 40px;
    text-align: center;
}

.contact-item h3 {
    font-size: 18px;
    margin-bottom: 5px;
    color: var(--dark-color);
}

.contact-item p {
    color: var(--text-light);
}

.form-group {
    margin-bottom: 20px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
}

.form-group textarea {
    height: 150px;
    resize: vertical;
}

/* 页脚样式 */
.footer {
    color: var(--white);
}

.bg-dark {
    background-color: var(--dark-color);
}

.footer-content {
    display: flex;
    flex-wrap: wrap;
    gap: 40px;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-logo {
    flex: 1;
    min-width: 250px;
}

.footer-logo a {
    font-size: 24px;
    font-weight: 700;
    color: var(--white);
    display: flex;
    align-items: center;
    margin-bottom: 15px;
}

.footer-logo i {
    margin-right: 10px;
    font-size: 28px;
    color: var(--primary-color);
}

.footer-logo p {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 20px;
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-links a {
    width: 40px;
    height: 40px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.social-links a:hover {
    background-color: var(--primary-color);
    transform: translateY(-3px);
}

.footer-links {
    flex: 2;
    min-width: 300px;
    display: flex;
    flex-wrap: wrap;
    gap: 40px;
}

.link-group {
    flex: 1;
    min-width: 150px;
}

.link-group h4 {
    font-size: 18px;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}

.link-group h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background-color: var(--primary-color);
}

.link-group ul li {
    margin-bottom: 10px;
}

.link-group ul li a {
    color: rgba(255, 255, 255, 0.7);
    transition: var(--transition);
}

.link-group ul li a:hover {
    color: var(--primary-color);
    padding-left: 5px;
}

.footer-bottom {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    padding-top: 30px;
    margin-top: 20px;
}

.copyright p {
    color: rgba(255, 255, 255, 0.7);
}

.friend-links {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
}

.friend-links a {
    color: rgba(255, 255, 255, 0.7);
    transition: var(--transition);
}

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

/* 返回顶部按钮 */
#back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 999;
}

#back-to-top.show {
    opacity: 1;
    visibility: visible;
}

#back-to-top:hover {
    background-color: #2980b9;
    transform: translateY(-3px);
}

/* 响应式设计 */
@media (max-width: 992px) {
    .hero-content h1 {
        font-size: 40px;
    }

    .section-header h2 {
        font-size: 32px;
    }
}

@media (max-width: 768px) {
    .nav {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background-color: var(--white);
        box-shadow: 0 5px 10px rgba(0, 0, 0, 0.1);
        transform: translateY(-150%);
        transition: var(--transition);
        z-index: 999;
    }

    .nav.active {
        transform: translateY(0);
    }

    .nav-links {
        flex-direction: column;
        padding: 20px;
    }

    .nav-links li {
        margin: 10px 0;
    }

    .mobile-nav-toggle {
        display: block;
    }

    .hero-content h1 {
        font-size: 36px;
    }

    .hero-content p {
        font-size: 18px;
    }

    .hero-content .btn {
        margin: 10px 0;
        display: block;
        width: 100%;
        max-width: 300px;
        margin-left: auto;
        margin-right: auto;
    }

    .about-content,
    .contact-content {
        flex-direction: column;
    }

    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }

    .friend-links {
        margin-top: 15px;
        justify-content: center;
    }
}

@media (max-width: 576px) {
    .hero-content h1 {
        font-size: 30px;
    }

    .section-header h2 {
        font-size: 28px;
    }

    .advantage-item,
    .feature-item {
        min-width: 100%;
    }

    .product-item,
    .news-item {
        min-width: 100%;
    }
}