body {
text-align: center;
}

#main_wrapper {
width: 792px;
margin-left: auto;
margin-right: auto;
text-align: left;
}
 
#header {
float: left;
}
 
#nav {
width: 18%;
float: left;
height: 418px;
}
 
#content {
width: 60%;
float: left;
}
 
#promo {
width: 22%;
float: left;
height: 418px;
}
 
#footer {
clear: both;
}
 
#header_inner, #nav_inner, #content_inner, #promo_inner {
overflow: hidden;
}
 
#header_inner {
padding: 1em 2em;
}
 
#nav_inner {
padding: 1em .8em;
border-right: 3px solid white;
}
 
#content_inner {
padding: 0 1em 1em 1.5em;
}
 
#footer_inner {
padding: .1em 1em;
text-align: center
}