1.<iframe src="toubu.html" width="100%" height="178px" ></iframe>将其他页面嵌入到本页面标签位置

2./*垂直居中*/ align-items: center;/*水平居中*/ text-align: center;

3./*轮廓线*/ outline: none;

4..head .line2 .search input:focus+span 定位到span元素

5./*focus获取焦点*/

.head .line2 .search input:focus{
background-position: 0 1px;
}