<div id="outer">div-outer <div id="inner-a">div-inner-a</div> <div id="inner-b">div-inner-b</div> <div id="inner-c">div-inner-c</div> </div>
#outer {overflow: auto; padding: 10px; background-color: #0000FF;}
#inner-a {float: left; width: 100px; background-color: #FFFF00;}
#inner-b {float: left; width: 100px; background-color: #00FF00;}
#inner-c {float: left; width: 100px; background-color: #FF0000;}