CSAg = window.navigator.userAgent; 
CSBVers = parseInt(CSAg.charAt(CSAg.indexOf("/")+1),10);

function IsIE() 
{ 
  return CSAg.indexOf("MSIE") > 0;
}

if(IsIE())
{   

  document.write('<link rel="stylesheet" href="includes/css/ie.css" type="text/css">');

} else {  

  document.write('<link rel="stylesheet" href="includes/css/netscape.css" type="text/css">');

}