css per netscape, internet explorer, opera

[LA VALE]

<SCRIPT language="JavaScript">
<!--
if (document.layers){ //Opera
document.write("<link rel='stylesheet' href='stile_opera.css' type='text/css'>");
}
else if (document.all){ // Explorer
document.write("<link rel='stylesheet' href='stile_explorer.css' type='text/css'>");
}
else if (document.getElementById){ //Netscape 6.x
document.write("<link rel='stylesheet' href='stile_netscape6.css' type='text/css'>");
}
//-->
</SCRIPT>


questo può andare???