function loadjscssfile(filename, filetype){
if (filetype=="css"){ //if filename is an external CSS file
  var fileref=document.createElement("link")
  fileref.setAttribute("rel", "stylesheet");
  fileref.setAttribute("type", "text/css");
  fileref.setAttribute("href", filename);
 }
 if (typeof fileref!="undefined")
  document.getElementsByTagName("head")[0].appendChild(fileref)
}

var filesadded="" //list of files already added

function checkloadjscssfile(filename, filetype){
 if (filesadded.indexOf("["+filename+"]")==-1){
  loadjscssfile(filename, filetype)
  filesadded+="["+filename+"]" //add to list of files already added, in the form of "[filename1],[filename2],etc"
 }
 else
  alert("file already added!")
}

var screen_height = screen.height;
var screen_width = screen.width;
if (screen_height > 768) {
	if (screen_height > 1050) {
		loadjscssfile("style3.css", "css");
	} else {
		loadjscssfile("style2.css", "css");
	}
} else {
loadjscssfile("style2.css", "css");
}