if 
((navigator.appVersion.indexOf("Mac") != -1) && (navigator.appName.indexOf("Firefox") != -1))
{ 
document.write('<link href="/stilmallar/css/macFIREFOX.css" rel="stylesheet" type="text/css">');
} 
else if 
((navigator.appVersion.indexOf("Mac") != -1) && (navigator.appName.indexOf("Safari") != -1))
{ 
document.write('<link rel="stylesheet" href="/stilmallar/css/macSAFARI.css" type="text/css">');
} 
else if 
((navigator.appVersion.indexOf("Win") != -1) && (navigator.appName.indexOf("Netscape") != -1))
{ 
document.write('<link rel="stylesheet" href="/stilmallar/css/winNS.css" type="text/css">');
} 
else if 
((navigator.appVersion.indexOf("Win") != -1) && (navigator.appName.indexOf("Firefox") != -1))
{ 
document.write('<link rel="stylesheet" href="/stilmallar/css/winFIREFOX.css" type="text/css">');
} 
else if 
((navigator.appVersion.indexOf("Win") != -1) && (navigator.appName.indexOf("Microsoft Internet Explorer") != -1))
{ 
document.write('<link rel="stylesheet" href="/stilmallar/css/winIE.css" type="text/css">');
} 
else 
{ 
document.write('<link rel="stylesheet" href="/stilmallar/css/annan.css" type="text/css">');
}