Intanto grazie mille per aver risposto,qui c'è il codice della pagina creata per fare il test:

codice:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="it" lang="it">
<head>
<title>Prova</title>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />

<style type="text/css">
#box1{
 float:right;
 width:450PX;
 background-color:#FBFFEA;
 color:#000000;
 border: 1px solid #000;
 font-size:13px;
 font-family: arial,sans-serif;
 margin-top:5px;
 margin-left:5px;
 margin-right:3px;
 margin-bottom:5px;
}

#box2{
 width:600px;
 height:270px;
 background-color:#7991A3;
 color:#000000;
 border:1px solid #000;
}
</style>
</head>

<body> 


<div id="box2">

<div id="box1">
















































</div>

</div>


</body>
</html>
Grazie ancora