if (/MSIE (\d+\.\d+);/.test(navigator.userAgent)){ //test for MSIE x.x;
 var ieversion=new Number(RegExp.$1) // capture x.x portion and store as a number
 if (ieversion>=7)
  document.write("<LINK href='/Style Library/style_ie7.css' type='text/css' rel='stylesheet'>")
 else if (ieversion>=6)
  document.write("<LINK href='/Style Library/style_ie6.css' type='text/css' rel='stylesheet'>")
}
else if (/Firefox[\/\s](\d+\.\d+)/.test(navigator.userAgent)){ //test for Firefox/x.x or Firefox x.x (ignoring remaining digits);
 var ffversion=new Number(RegExp.$1) // capture x.x portion and store as a number
 if (ffversion>=2)
  document.write("<LINK href='/Style Library/style_ff_safari.css' type='text/css' rel='stylesheet'>")
} else
 document.write("<LINK href='/Style Library/style_ff_safari.css' type='text/css' rel='stylesheet'>")