*{margin:0;padding:0;} 
body{padding:50px;}
div{width:60px;height:30px;border:1px solid #ddd; border-radius:15px;cursor: pointer;}
div span{width:30px;height:30px;border:1px solid #ddd;border-radius:15px;display:block;margin:-1px;}
div.on{background:#eee}
div.on span{margin-left:29px;background:#1E9FFF;border-color:#1E9FFF}