div#header{
    position:relative
}
div#navigation{
    /* background:#B9CAFF */
}
div#extra{
    /* background:#FF8539 */
}

div#container{
    width:960px;
    margin:0 auto
}
div#content{
    float:left;
    width:660px
}
div#navigation{
    float:right;
    width:300px
}
div#extra{
    clear:both;
    width:100%
}