让若干个div排成一起

让若干个div排成一行

<div>   <div style="float:left;width:100px;border:1px solid red">1</div>   <div style="float:left;width:100px;border:1px solid blue">2</div>   <div style="float:left;width:100px;border:1px solid green">3</div></div>