Ok, for this small amount of code

Code:
<div id="centersite"> 
 <div id="logo"> 
   <h1>Premier Logistics</h1>
  </div>
and my css as this

Code:
<!--
#logo {
 background-image: url(roadheader.jpg);
 background-repeat: no-repeat;
 background-position: left top;
 height: 159px;
 width: 700px;
 margin: 0px;
}
body {
 margin: 0px;
 background-color: #F5F5F5;
 padding: 0px;
}
#logo h1 {
 margin: 0px 400px 0px 25px;
 padding: 2px;
 background-color: #FFFFFF;
 border: 1px solid #000000;
 text-align: center;
}
#centersite {
 margin-right: auto;
 margin-left: auto;
 width: 700px;
 margin-top: 0px;
 margin-bottom: 0px;
}
-->
If I add about 15px of margin for the #logo h1 for the top, it actually pushes the whole thing down 15 pixels, rather then just push the h1 down 15 pixels

Really weird. If I set it to 0px, the whole site hugs the top, which I want.