body{background:pink;}
 #wrapper{width:1000px;height:1000px;background:lightgreen;}

#header{width:100%;height:15%;background:yellow;}

#header h1{font-size:80px;margin:10px auto;padding:30px;}

#inner_wrapper{width:80%;height:20%;margin:10px auto;padding:0px;}

#footer{width:100%;height:20%;background:red;}
#one{width:330px;height:100px;background:gray;float:left;}
#two{width:330px;height:100px;background:cyan;float:left;}
#three{width:340px;height:100px;background:red;float:left;}