/* 全局样式 */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'Microsoft YaHei', sans-serif; line-height: 1.6; color: #333; background: #f4f6f9; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }

/* 页眉 */
header { background: #fff; box-shadow: 0 2px 10px rgba(0,0,0,0.08); position: sticky; top: 0; z-index: 1000; }
.header-container { max-width: 1200px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; padding: 0 20px; height: 70px; }
.logo { font-size: 22px; font-weight: bold; color: #0056b3; display: flex; align-items: center; }
.logo img { height: 36px; margin-right: 12px; }
.nav { display: flex; }
.nav-item { position: relative; padding: 25px 15px; cursor: pointer; transition: color 0.3s; }
.nav-item:hover { color: #0056b3; }
.nav-item > a { font-size: 16px; font-weight: 500; }

/* 下拉菜单 */
.dropdown { display: none; position: absolute; top: 100%; left: 0; background: #fff; box-shadow: 0 5px 15px rgba(0,0,0,0.12); min-width: 200px; border-radius: 6px; padding: 8px 0; z-index: 1001; }
.nav-item:hover .dropdown { display: block; }
.dropdown a { display: block; padding: 12px 20px; font-size: 14px; transition: background 0.2s, color 0.2s; }
.dropdown a:hover { background: #eef5ff; color: #0056b3; }

/* 主内容区 */
main { max-width: 1200px; margin: 40px auto; padding: 0 20px; min-height: 65vh; }
h1 { font-size: 30px; margin-bottom: 25px; color: #0056b3; text-align: center; }
h2 { font-size: 22px; margin: 35px 0 15px; color: #222; border-left: 4px solid #0056b3; padding-left: 12px; }
p { margin-bottom: 15px; text-align: justify; color: #444; }
img { max-width: 100%; height: auto; display: block; }

/* 首页卡片 */
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 30px; margin-top: 30px; }
.card { background: #fff; padding: 30px; border-radius: 10px; box-shadow: 0 4px 12px rgba(0,0,0,0.05); transition: transform 0.3s, box-shadow 0.3s; }
.card:hover { transform: translateY(-6px); box-shadow: 0 8px 20px rgba(0,0,0,0.1); }
.card h3 { margin-bottom: 12px; color: #0056b3; font-size: 18px; }

/* 产品卡片 */
.product-card { background: #fff; border-radius: 10px; overflow: hidden; box-shadow: 0 4px 12px rgba(0,0,0,0.05); transition: transform 0.3s; }
.product-card:hover { transform: translateY(-5px); }
.product-card img { width: 100%; height: 220px; object-fit: cover; background: #e0e0e0; }
.product-card .info { padding: 25px; }
.product-card h3 { margin-bottom: 12px; font-size: 18px; color: #333; }
.specs ul { margin-top: 10px; padding-left: 18px; list-style: disc; color: #555; }
.specs li { margin-bottom: 6px; font-size: 14px; }

/* 联系信息 */
.contact-info { background: #fff; padding: 50px 40px; border-radius: 10px; box-shadow: 0 4px 15px rgba(0,0,0,0.06); max-width: 600px; margin: 0 auto; text-align: center; }
.contact-item { margin: 25px 0; font-size: 18px; color: #333; }
.contact-item strong { color: #0056b3; margin-right: 10px; }

/* 页脚 */
footer { background: #233a7bc8; color: #ecf0f1; text-align: center; padding: 25px; margin-top: 60px; font-size: 14px; }