* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Microsoft YaHei", sans-serif;
}

ul {
    list-style: none;
}

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



img {
    width: 100%;
    display: block;
}
.btn {
    display: inline-block;
    padding: 12px 28px;
    background: #0066cc;
    color: #fff;
    border-radius: 4px;
    transition: 0.3s;
}

    .btn:hover {
        background: #004b99;
    }

.star {
    color: red;
}
/* 导航栏 */
header {
    width: 100%;
    height: 60px;
    background: #fff;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 999;
}

.nav-wrap {
    width: 90%;
    max-width: 1200px;
    height: 100%;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 24px;
    font-weight: bold;
    color: #2563eb;
}

.nav-list {
    display: flex;
    gap: 35px;
}

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

        .nav-list li a:hover {
            color: #2563eb;
        }

/* 轮播图核心样式 - 自适应多端 */
.banner {
    width: 100%;
    /* 核心：宽高比自适应，PC端默认高600px，移动端按比例缩放 */
    height: 600px;
    max-width: 1920px;
    margin: 0 auto;
    overflow: hidden;
    position: relative;
}

.banner-track {
    display: flex;
    height: 100%;
    transition: transform 0.7s ease-in-out;
}

.banner-item {
    min-width: 100%;
    height: 100%;
}

/* 轮播图片自适应 - 单张图片适配多端 */
.banner-img {
    width: 100%;
    height: 100%;
    /* 保持图片比例，铺满容器不拉伸，裁剪溢出部分（可选：object-fit: contain 不裁剪但留空白） */
    object-fit: cover;
}

/* 左右切换按钮 */
.banner-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 46px;
    height: 46px;
    border-radius: 50%;
    border: none;
    background: rgba(255,255,255,0.35);
    color: #fff;
    font-size: 20px;
    cursor: pointer;
    z-index: 10;
    transition: background 0.3s;
}

    .banner-btn:hover {
        background: rgba(255,255,255,0.7);
        color: #333;
    }

.prev-btn {
    left: 30px;
}

.next-btn {
    right: 30px;
}

/* 圆点指示器 */
.dots-box {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 12px;
}

.dot {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: rgba(255,255,255,0.4);
    cursor: pointer;
}

    .dot.active {
        background: #fff;
    }

/* 移动端适配（768px以下） */
@media screen and (max-width: 768px) {
    /* 轮播容器高度自适应 - 按屏幕宽度比例缩放 */
    .banner {
        /* 可选1：固定移动端高度 */
        height: 200px;
        /* 可选2：按宽高比自适应（推荐），例如 16:9 比例：height: calc(100vw * 9 / 16); */
        /* height: calc(100vw * 9 / 16); */
    }

    /* 按钮尺寸适配 */
    .banner-btn {
        width: 36px;
        height: 36px;
        font-size: 16px;
    }

    .prev-btn {
        left: 15px;
    }

    .next-btn {
        right: 15px;
    }

    /* 圆点尺寸适配 */
    .dots-box {
        bottom: 15px;
    }

    .dot {
        width: 10px;
        height: 10px;
    }
}

/* 通用容器 */
.container {
    width: 90%;
    max-width: 1200px;
    margin: 80px auto;
}

.title {
    text-align: center;
    font-size: 32px;
    color: #222;
    margin-bottom: 50px;
    position: relative;
}

    .title::after {
        content: "";
        width: 70px;
        height: 4px;
        background: #2563eb;
        position: absolute;
        left: 50%;
        transform: translateX(-50%);
        bottom: -12px;
    }

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

.about-img {
    width: 50%;
    border-radius: 8px;
    overflow: hidden;
}

.about-text {
    width: 50%;
    font-size: 16px;
    line-height: 2;
    color: #555;
}

/* 产品展示 */
.product-list {
    display: flex;
    gap: 30px;
}

.product-item {
    flex: 1;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 3px 12px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

    .product-item:hover {
        transform: translateY(-8px);
    }

    .product-item h3 {
        text-align: center;
        padding: 15px 0;
        color: #333;
    }

/* 联系我们 */
.contact-wrap {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.contact-info h3, .contact-form h3 {
    font-size: 22px;
    margin-bottom: 20px;
}

.contact-info p {
    margin: 10px 0;
    color: #444;
}

.contact-form input, .contact-form textarea {
    width: 100%;
    padding: 12px;
    margin-bottom: 15px;
    border: 1px solid #ddd;
    border-radius: 4px;
    outline: none;
}

.submit-btn {
    border: none;
    cursor: pointer;
    width: 100%;
}

/* 底部 */
footer {
    width: 100%;
    height: 120px;
    background: #1f2937;
    color: #aaa;
    text-align: center;
    line-height: 120px;
    font-size: 15px;
}

/* 手机适配 */
@media screen and (max-width:768px) {
    .nav-list {
        display: none;
    }

    .banner {
        height: 190px;
    }

    .about-box {
        flex-direction: column;
    }

    .about-img, .about-text {
        width: 100%;
    }

    .product-list {
        flex-direction: column;
    }
}