var browserName=navigator.appName;

 if (browserName=="Netscape")
{ 
 document.write("<LINK REL=stylesheet HREF=style_nouv.css TYPE=text/css>");
}
else 
{ 
 if (browserName=="Microsoft Internet Explorer")
 {
 document.write("<LINK REL=stylesheet HREF=IEstyle_nouv.css TYPE=text/css>");
 }
 else
    {
       if (browserName=="Opera")
       {
       document.write("<LINK REL=stylesheet HREF=OPstyleRessources.css TYPE=text/css>");
       }
       else
        {
        document.write("<LINK REL=stylesheet HREF=style_nouv.css TYPE=text/css>");
        }
    }
}