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

body {
    font-family: 'Microsoft YaHei', 'Heiti SC', 'Noto Sans SC', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f9f9f9;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 15px;
}

a {
    text-decoration: none;
    color: #0056b3;
    transition: color 0.3s ease;
}

a:hover {
    color: #003d7a;
}

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

.btn {
    display: inline-block;
    background-color: #0056b3;
    color: #fff;
    padding: 10px 25px;
    border-radius: 5px;
    transition: background-color 0.3s ease;
    font-weight: 500;
    text-align: center;
}

.btn:hover {
    background-color: #003d7a;
    color: #fff;
}

.section-title {
    text-align: center;
    margin-bottom: 40px;
    color: #0056b3;
    position: relative;
    padding-bottom: 15px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background-color: #0056b3;
}

/* 头部导航 */
header {
    background-color: #fff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

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

.logo h1 {
    font-size: 1.8rem;
    margin: 0;
    color: #0056b3;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 30px;
}

nav ul li a {
    color: #333;
    font-weight: 500;
    padding: 5px 0;
    position: relative;
}

nav ul li a:hover,
nav ul li a.active {
    color: #0056b3;
}

nav ul li a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: #0056b3;
    transition: width 0.3s ease;
}

nav ul li a:hover::after,
nav ul li a.active::after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
}

/* 英雄区域 */
.hero {
    background: linear-gradient(rgba(0, 86, 179, 0.8), rgba(0, 61, 122, 0.8)), url('../img/hero-bg.jpg');
    background-size: cover;
    background-position: center;
    color: #fff;
    padding: 100px 0;
    text-align: center;
}

.hero-content {
    max-width: 700px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.hero h2 {
    font-size: 1.8rem;
    font-weight: 400;
    margin-bottom: 20px;
}

.hero p {
    font-size: 1.1rem;
    margin-bottom: 30px;
}

.hero .btn {
    background-color: #fff;
    color: #0056b3;
}

.hero .btn:hover {
    background-color: #f0f0f0;
}

/* 产品预览区域 */
.products-preview {
    padding: 80px 0;
    background-color: #fff;
}

.product-categories {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.category {
    background-color: #f9f9f9;
    border-radius: 5px;
    overflow: hidden;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.category:hover {
    transform: translateY(-10px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.category img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.category h3 {
    padding: 15px 15px 10px;
    font-size: 1.2rem;
    color: #0056b3;
}

.category p {
    padding: 0 15px 15px;
    color: #666;
}

.view-more {
    text-align: center;
}

/* 关于我们预览区域 */
.about-preview {
    padding: 80px 0;
    background: linear-gradient(rgba(0, 86, 179, 0.05), rgba(0, 86, 179, 0.05)), #f9f9f9;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-content p {
    margin-bottom: 20px;
    color: #555;
}

/* 联系我们预览区域 */
.contact-preview {
    padding: 80px 0;
    background-color: #fff;
}

.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.info-item {
    text-align: center;
    padding: 20px;
    background-color: #f9f9f9;
    border-radius: 5px;
    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
}

.info-item i {
    font-size: 2.5rem;
    color: #0056b3;
    margin-bottom: 15px;
}

.info-item h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: #0056b3;
}

.info-item p {
    color: #666;
}

/* 页脚 */
footer {
    background-color: #0056b3;
    color: #fff;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-logo h2 {
    font-size: 1.5rem;
    margin-bottom: 10px;
}

.footer-logo p {
    color: rgba(255, 255, 255, 0.8);
}

.footer-links h3,
.footer-contact h3 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    position: relative;
    padding-bottom: 10px;
}

.footer-links h3::after,
.footer-contact h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background-color: #fff;
}

.footer-links ul {
    list-style: none;
}

.footer-links ul li {
    margin-bottom: 10px;
}

.footer-links ul li a {
    color: rgba(255, 255, 255, 0.8);
    transition: color 0.3s ease, padding-left 0.3s ease;
}

.footer-links ul li a:hover {
    color: #fff;
    padding-left: 5px;
}

.footer-contact p {
    margin-bottom: 10px;
    color: rgba(255, 255, 255, 0.8);
}

.footer-contact i {
    margin-right: 10px;
    width: 20px;
    text-align: center;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    padding-top: 20px;
    text-align: center;
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
}

.footer-bottom p {
    margin-bottom: 5px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .mobile-menu-btn {
        display: block;
    }

    nav {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        background-color: #fff;
        box-shadow: 0 5px 10px rgba(0, 0, 0, 0.1);
        transition: left 0.3s ease;
        height: calc(100vh - 70px);
        overflow-y: auto;
    }

    nav.active {
        left: 0;
    }

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

    nav ul li {
        margin: 0 0 15px 0;
    }

    nav ul li a {
        display: block;
        padding: 10px 0;
    }

    .hero {
        padding: 60px 0;
    }

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

    .hero h2 {
        font-size: 1.5rem;
    }

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

@media (max-width: 576px) {
    .hero h1 {
        font-size: 1.8rem;
    }

    .hero h2 {
        font-size: 1.3rem;
    }

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

    .section-title {
        font-size: 1.5rem;
    }
}