var mybrowser = navigator.userAgent; // navigator.userAgent (gets browser info).
if(mybrowser.indexOf('MSIE') != -1) { //find browser info(navigator.userAgent), search for "Safari", if browser is Safari then return not equal to -1 (continue to line 3). If browser is NOT Safari, return -1 (skip line 3).
document.write('<link href="explorer_style.css" rel="stylesheet" type="text/css" />');
}else if(mybrowser.indexOf('Firefox') != -1) {
	document.write('<link href="firefox_style.css" rel="stylesheet" type="text/css" />');
}else if(mybrowser.indexOf('Safari') != -1) {
	document.write('<link href="safari_style.css" rel="stylesheet" type="text/css" />' );
}