<style>
body,html {
height:100%;
margin:0;
background:#000; }
#box {
width:400px; height:400px;
position:absolute;
top:50%;left:50%;
margin:-200px 0 0 -200px;
border:1px solid #000;
background-color:#f00;
overflow:auto;
}
</style>

<html><body scroll=no>



<div id="box">
testo contenuto







qqq
</div>
</body>
</html>