单行一列以下是引用片段:body{margin:0px;padding:0px;text-align:center;} #content{margin-left:auto;margin-right:auto;width:400px;width:370px;}两行一列以下是引用片段:body{margin:0px;padding:0px;text-align:center;} #content-top{margin-left:auto;margi