Following page: http://www.goldenwillowcavaliers.com/

works fine in Safari, Firefox; but does not center in IE. I have validated both the XHTML and CSS at W3C.

CSS file:

body{
margin:0;
padding:0;
background-color:#fff;
background-image:url(../images/main_dogBG.png);
background-repeat:no-repeat;
background-position:bottom left;
}

#header {
width:900px;
height: 80px;
}

#content {
padding:0;
margin:2px auto;
background-image:url(../images/contentBG.png);
background-repeat:repeat;
background-position:top;
border:1px solid #333;
width:900px;
min-height:500px;
}

#nav {
height:20px;
background-color:#3B7E45;
width:900px;
}

#nav ul {
margin:0;
padding:0;
}

#nav ul li {
display:inline;
}

#nav ul li a:link {
color:#FFF;
font-weight:bold;
padding: 0 30px;
text-decoration:none;
}
#nav ul li a:visited {
color:#FFF;
font-weight:bold;
padding: 0 30px;
text-decoration:none;
}
#nav ul li a:hover {
color:#C2C659;
font-weight:bold;
padding: 0 30px;
text-decoration:none;
}
#nav ul li a:active {
color:#A3433A;
font-weight:bold;
padding: 0 30px;
text-decoration:none;
}


#main {
margin-left:14px;
clear:left;
height:580px;
}

#footer {
float:left;
width:900px;
border-top:1px solid #333;
height:18px;
background-color:#67B873;
color:#333;
font-size:9px;
}

#footer p {
padding:0;
margin:5px 0 0 5px;
}

#footer a {
color:#000;
}