#banner { }
#columns { position: relative; }
#main { margin-left: 12em; margin-right: 12em; }
#nav { position: absolute; top: 1em; left: 1em; width: 10em; }
#side { position: absolute; top: 1em; right: 1em; width: 10em; }
#footer { }

IMG.displaycenter {
    display: block;
    margin-left: auto;
    margin-right: auto }