Something

#container
{
width: 90%;
margin: 10px auto;
background-color: #F2F2F2;
border: 1px solid #DDDDDD;
}

#header
{
padding: .5em;
border-bottom: 1px solid grey;
}

#header h1
{
padding: 0;
margin: 0;
}

#nav
{
float: left;
width: 160;
margin: 0;
padding: 1em;
}

#content
{
float: left;
margin-left: 160px;
border-left: 1px solid grey;
}

#footer
{
clear: both;
padding: .5em;
border-top: 1px solid grey;
}