var altezza = window.screen.availHeight - (window.screen.availHeight/2);
document.write('<DIV STYLE="position:absolute;  top:0px; left:210px; visibility:visible">');
document.write('<center>');
document.write('<table  width="600" height="'+ altezza +'" bgcolor="#ffffff" bordercolor="#C3C4C8" cellspacing="0" cellpadding="0" border="1" width="641" height="75">');
document.write('<tr  class="testo" >');
document.write('<td class="testojust">');
document.write('<IFRAME name="downf" frameborder="0"  marginwidth="0" marginhEighT="0" width="650" height="'+ altezza +'" SRC="contenuti.php?arg=home">');
document.write('</IFRAME>');
document.write('</td>');
document.write('</tr>');
document.write('</table>');
document.write('</center>');
document.write('</DIV>');