/* 全局通用样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Microsoft Yahei",sans-serif;
}
body {
    color: #333;
    line-height: 1.7;
}
.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 60px 0;
}
h2 {
    text-align: center;
    font-size: 28px;
    margin-bottom: 40px;
    color: #111;
    position: relative;
}
h2::after {
    content: "";
    display: block;
    width: 80px;
    height: 3px;
    background: #c81623;
    margin: 12px auto 0;
}
.bg-gray {
    background: #f5f5f5;
}
.btn {
    display: inline-block;
    background: #c81623;
    color: #fff;
    padding: 12px 30px;
    text-decoration: none;
    border-radius: 4px;
    margin-top: 20px;
    transition: 0.3s;
}
.btn:hover {
    background: #a0101c;
}

/* 导航栏 */
.nav-bar {
    background: #111;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 999;
}
.nav-bar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}
.logo {
    color: #fff;
    font-size: 20px;
    font-weight: bold;
}
.nav-menu a {
    color: #fff;
    text-decoration: none;
    margin-left: 30px;
    font-size: 15px;
}
.nav-menu a:hover {
    color: #c81623;
}

/* 横幅 */
.banner {
    height: 100vh;
    background: linear-gradient(rgba(0,0,0,0.6),rgba(0,0,0,0.6)),url(images/banner.jpg) center/cover no-repeat;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: #fff;
    padding-top: 60px;
}
.banner-text h1 {
    font-size: 48px;
    margin-bottom: 15px;
}
.banner-text p {
    font-size: 20px;
    opacity: 0.9;
}

/* 优势板块 */
.adv-list {
    display: grid;
    grid-template-columns: repeat(4,1fr);
    gap: 25px;
}
.adv-item {
    text-align: center;
    padding: 30px 20px;
    border: 1px solid #eee;
    border-radius: 6px;
}
.adv-item h3 {
    margin-bottom: 12px;
    color: #c81623;
}

/* 关于我们 */
.about-text {
    font-size: 16px;
    line-height: 2;
    text-indent: 2em;
}

/* 产品板块 */
.product-list {
    display: grid;
    grid-template-columns: repeat(3,1fr);
    gap: 25px;
}
.product-item {
    padding: 25px;
    background: #fff;
    box-shadow: 0 2px 10px #eee;
    border-radius: 6px;
}
.product-item h3 {
    color: #c81623;
    margin-bottom: 10px;
}

/* 工厂实力 */
.factory-list {
    font-size: 17px;
    line-height: 2.2;
    padding-left: 20px;
}

/* 联系我们 */
.contact-info {
    text-align: center;
    font-size: 18px;
    line-height: 2.5;
}

/* 底部 */
.footer {
    background: #111;
    color: #aaa;
    text-align: center;
    padding: 20px 0;
    font-size: 14px;
}

/* 移动端适配（手机自动排版） */
@media (max-width:768px) {
    .adv-list,.product-list {
        grid-template-columns: 1fr;
    }
    .banner-text h1 {
        font-size: 32px;
    }
    .nav-menu a {
        margin-left: 10px;
        font-size: 13px;
    }
}