/* 
 * 中国建材采购网 - 统一样式表
 * 风格：稳重、专业、工业感
 * 配色：#5d4037 (建材棕), #607d8b (板岩灰), #fafafa (底色)
 */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: "SimSun", "Microsoft YaHei", serif; font-size: 14px; color: #333; line-height: 1.6; background: #f4f4f4; }
a { text-decoration: none; color: #333; transition: 0.2s; }
a:hover { color: #5d4037; }
ul { list-style: none; }

.container { width: 1200px; margin: 0 auto; background: #fff; }

/* 头部 */
.header-top { background: #5d4037; color: #fff; padding: 8px 0; font-size: 12px; }
.header-main { padding: 30px 40px; display: flex; justify-content: space-between; align-items: center; border-bottom: 4px solid #5d4037; }
.logo h1 { font-size: 30px; color: #5d4037; font-weight: bold; border-left: 10px solid #5d4037; padding-left: 20px; }

/* 导航 */
.nav { background: #607d8b; display: flex; }
.nav li a { display: block; padding: 15px 30px; color: #fff; font-size: 16px; font-weight: bold; }
.nav li a:hover, .nav li.active a { background: #5d4037; }

/* 首页布局 */
.main-wrap { padding: 30px 40px; display: grid; grid-template-columns: 250px 1fr 250px; gap: 20px; }
.category-box { border: 1px solid #ddd; }
.category-title { background: #5d4037; color: #fff; padding: 10px 15px; font-weight: bold; }
.category-list li { padding: 10px 15px; border-bottom: 1px dashed #eee; font-size: 13px; }
.category-list li:hover { background: #fafafa; }

/* 资讯网格 */
.bm-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.bm-item { display: flex; gap: 15px; padding: 15px; border: 1px solid #eee; transition: 0.3s; }
.bm-item:hover { border-color: #5d4037; box-shadow: 0 5px 15px rgba(0,0,0,0.05); }
.bm-img { width: 120px; height: 100px; flex-shrink: 0; overflow: hidden; }
.bm-img img { width: 100%; height: 100%; object-fit: cover; }
.bm-info h3 { font-size: 15px; margin-bottom: 8px; height: 44px; overflow: hidden; }

/* 内容页 */
.article-wrap { padding: 40px 60px; }
.article-header { border-bottom: 2px solid #5d4037; padding-bottom: 20px; margin-bottom: 30px; }
.article-header h1 { font-size: 26px; color: #5d4037; }
.article-body { font-size: 16px; line-height: 2; color: #444; }
.article-body p { margin-bottom: 25px; }

/* 页脚 */
.footer { background: #444; color: #bbb; padding: 60px 0; margin-top: 50px; text-align: center; }
.footer-links { margin-bottom: 20px; }
.footer-links a { color: #bbb; margin: 0 15px; }
.footer-copyright { font-size: 12px; border-top: 1px solid #555; padding-top: 20px; width: 800px; margin: 0 auto; }