Salve sto iniziando a creare questo sito su IE sembra che tutto sia ok, mentre su FF noto ke mi crea un bordo sotto il div del top.

ecco il css:
codice:
html,body{margin:0 auto; height: 100%;}

body{
	background: url(img/sf_02.png);
	font-family: Verdana;
             font-size: 76%;   /*dimensionamento percentuale del font */
	color:#FFFFFF;
             text-align: center;   /*centra in IE 5.x */
    }

	
div#content{
	margin: 0 auto;
	position: relative;
	width:1000px;
	/*text-align: left;*/
	/*align:center;*/
    }
	
div#container{
	position: relative;
	width:100%;
	text-align: center;
	margin-top:0px;
    }

div#pagina{
	position: relative;
	top: 0px; /*l' altezza dell' header*/
    width: 1000px;
	text-align:justify;
    }
	
div#pagina_sopra{
	position: relative;
	background: url(img/paginetta_05.png);
	top: 0px; /*l' altezza dell' header*/
    width: 575px;
	height:500px;
	/*min-height:500px;
	max-height:611px;*/
	text-align:justify;
    }
	
div#pagina_sotto{
	position: relative;
	background: url(img/paginetta_08.png);
	top: 0px; /*l' altezza dell' header*/
    width: 575px;
	text-align:justify;
    }
	
div#logo{
	position: absolute;
	background: url(img/paginetta_06.png);
	top: 342px; /*l' altezza dell' header*/
	left:575px;
    width: 425px;
	height:117px;
	text-align:justify;
    }
	

div#space{
	position: relative;
    width: 10px;
	height: 80px;
	bottom:0px;
	text-align:left;
    }
	
	
div#top{
	position: relative;
	width: 1000px;
	height:327px;
	margin-top:15px;
    }
	
div#sf{
	position: absolute;
    width: 100%;
	top:0px;
	background-image:url(img/sf_01.png);
	height:720px;
    }
		
.puls{
	font-family: Verdana;
	font-size: 100%;   /*dimensionamento percentuale del font */
	text-align: center;   /*centra in IE 5.x */
	vertical-align:middle;
	color:#FFFFFF;
}

a:link{
	color: #FFFFFF;
	text-decoration: none;
}

a:visited{
	color: #FFFFFF;
	text-decoration: none;
}

a:hover{
	color: #FFFFFF;
	font-weight: bold;
}
ecco invece l'HTML
codice:
<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Title</title>
<link href="style.css" rel="stylesheet" type="text/css" />
</head>

<body>
<div id="sf"></div>
<div id="container">
<div id="content">
<div id="top">[img]img/top_03.jpg[/img]</div>
<div id="pagina">
<div id="pagina_sopra">
Testo
</div>
<div id="pagina_sotto"></div>
</div>
<div id="logo"></div>
</div>
</div>
</body>
</html>