function osBrowserDetection(){
var userAgent = window.navigator.userAgent.toLowerCase();
var ieVersion = window.navigator.appVersion.toLowerCase();
var osCss;
var browserCss;
if(userAgent.indexOf('win') > -1){
osCss = 'win.css';
}else if(userAgent.indexOf('mac') > -1){
osCss = 'mac.css';
}else if(userAgent.indexOf('x11') > -1){
osCss = 'x11.css';
}
document.write('<link rel="stylesheet" href="css/'+ osCss + '" type="text/css" />');
if (userAgent.indexOf('msie') > -1) {
if (ieVersion.indexOf('msie 6.0') > -1) {
alert('IE6');
}else if (ieVersion.indexOf('msie 7.0') > -1) {
alert('IE7');
}else if (ieVersion.indexOf('msie 8.0') > -1) {
alert('IE8');
}else {
alert('Unknown');
}
}else if (userAgent.indexOf('firefox') > -1) {
alert('Firefox');
}else if (userAgent.indexOf('opera') > -1) {
alert('Opera');
}else if (userAgent.indexOf('chrome') > -1) {
alert('Google Chrome');
}else if (userAgent.indexOf('safari') > -1) {
alert('Safari');
}else {
alert('Unknown');
}
}
window.onload = osBrowserDetection;