* { margin:0; padding:0; box-sizing:border-box; font-family:"Microsoft YaHei"; }
body { color:#333; background:#f9f9f9; }
a { text-decoration:none; color:#333; }
.container { width:100%; max-width:1200px; margin:0 auto; padding:0 15px; }

/* 头部 */
.header { background:#fff; box-shadow:0 2px 5px rgba(0,0,0,0.05); padding:15px 0; }
.header .container { display:flex; justify-content:space-between; align-items:center; }
.logo { font-size:22px; font-weight:bold; color:#0052cc; }
.nav { display:flex; list-style:none; gap:30px; }
.nav li a { font-size:16px; color:#333; }
.nav li.active a { color:#0052cc; font-weight:bold; }

/* 轮播 */
.banner {
  background: linear-gradient(135deg, #004899, #239955);
  color:#fff; padding:80px 0;
}
.banner-text h2 { font-size:42px; margin-bottom:15px; }
.banner-text p { font-size:18px; margin-bottom:25px; opacity:0.9; }
.btn {
  background:#fff; color:#0052cc;
  padding:12px 30px; border-radius:4px;
  font-weight:bold; display:inline-block;
}

/* 产品 */
.product-section { padding:60px 0; background:#fff; }
.title { text-align:center; margin-bottom:40px; }
.title h3 { font-size:30px; color:#004899; margin-bottom:8px; }
.product-list {
  display:grid;
  grid-template-columns:repeat(4,1fr);
  gap:25px;
}
.item { background:#f5f7fa; padding:20px; border-radius:8px; text-align:center; }
.item img { width:100%; height:160px; object-fit:cover; border-radius:6px; margin-bottom:15px; }
.item h4 { font-size:18px; margin-bottom:8px; color:#222; }
.item p { font-size:14px; color:#666; line-height:1.5; }

/* 底部 */
.footer { background:#002244; color:#fff; text-align:center; padding:30px 0; margin-top:50px; }

/* 手机自适应 */
@media(max-width:992px){
  .product-list { grid-template-columns:repeat(2,1fr); }
  .banner-text h2 { font-size:28px; }
  .nav { display:none; }
}
@media(max-width:576px){
  .product-list { grid-template-columns:1fr; }
}