/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "微软雅黑", "PingFang SC", sans-serif;
}

body {
    color: #333;
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: #333;
}

/* 导航栏 */
.navbar {
    background-color: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    font-size: 24px;
    font-weight: bold;
    color: #2d8cf0;
}

.nav-links {
    display: flex;
    list-style: none;
}

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

.nav-links a {
    font-size: 16px;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: #2d8cf0;
}

/* 按钮 */
.btn {
    display: inline-block;
    background-color: #2d8cf0;
    color: #fff !important;
    padding: 10px 20px;
    border-radius: 4px;
    border: none;
    cursor: pointer;
    transition: background-color 0.3s;
}

.btn:hover {
    background-color: #1c7ed6;
}

.btn-sm {
    padding: 6px 12px;
    font-size: 14px;
}

/* 横幅 */
.banner {
    background: linear-gradient(135deg, #2d8cf0, #5cadff);
    color: #fff;
    padding: 80px 20px;
    text-align: center;
}

.banner-content h1 {
    font-size: 36px;
    margin-bottom: 20px;
}

.banner-content p {
    font-size: 18px;
    margin-bottom: 30px;
}

/* 通用区块 */
.advantages, .product-preview, .about, .products, .contact {
    padding: 60px 20px;
    max-width: 1200px;
    margin: 0 auto;
}

h2 {
    text-align: center;
    margin-bottom: 40px;
    font-size: 30px;
    color: #333;
    position: relative;
}

h2::after {
    content: "";
    display: block;
    width: 80px;
    height: 3px;
    background-color: #2d8cf0;
    margin: 10px auto;
}

/* 核心优势 */
.advantage-list {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 20px;
}

.advantage-item {
    flex: 1;
    min-width: 280px;
    padding: 30px;
    background-color: #f8f9fa;
    border-radius: 8px;
    text-align: center;
}

.advantage-item h3 {
    color: #2d8cf0;
    margin-bottom: 15px;
    font-size: 20px;
}

/* 产品预览 */
.product-list {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 30px;
}

.product-item {
    width: 300px;
    text-align: center;
}

.product-item img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 15px;
}

.product-item h3 {
    margin-bottom: 10px;
}

/* 关于我们 */
.about-content {
    max-width: 800px;
    margin: 0 auto;
    line-height: 1.8;
}

.about-content h3 {
    margin: 25px 0 15px;
    color: #2d8cf0;
}

.timeline {
    list-style: none;
    margin: 20px 0;
}

.timeline li {
    margin: 10px 0;
    padding-left: 20px;
    position: relative;
}

.timeline li::before {
    content: "●";
    color: #2d8cf0;
    position: absolute;
    left: 0;
}

/* 产品介绍 */
.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.product-card {
    background-color: #f8f9fa;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

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

.product-info {
    padding: 20px;
}

.product-info h3 {
    color: #2d8cf0;
    margin-bottom: 15px;
}

/* 联系方式 */
.contact-container {
    display: flex;
    flex-wrap: wrap;
    gap: 40px;
    max-width: 800px;
    margin: 0 auto;
}

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

.contact-info h3, .contact-form h3 {
    margin-bottom: 20px;
    color: #2d8cf0;
}

.contact-info p {
    margin: 10px 0;
}

.contact-form input, .contact-form textarea {
    width: 100%;
    padding: 10px;
    margin-bottom: 15px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
}

/* 底部 */
.footer {
    background-color: #333;
    color: #fff;
    padding: 30px 20px;
    text-align: center;
    margin-top: 40px;
}

.footer-content p {
    margin: 5px 0;
    font-size: 14px;
}

/* 响应式适配（手机端） */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        height: auto;
        padding: 20px;
    }

    .nav-links {
        margin-top: 15px;
    }

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

    .banner-content h1 {
        font-size: 28px;
    }

    h2 {
        font-size: 24px;
    }
}