function reportSize() {
  myWidth = 0, myHeight = 0; 
  
  	//1048 x 699 base size of images;
  imgWdith = 900;
  imgHeight = 600;
  
	myWidth = document.documentElement.clientWidth;
    myHeight = document.documentElement.clientHeight;
	
	newWidth = myWidth;
	newHeight = myHeight;

	
	if(myWidth > myHeight){
			newHeight = imgHeight * (myWidth / imgWdith );
			
			if(newHeight < myHeight){
				newHeight = myHeight;
				newWidth = imgWdith *  (myHeight / imgHeight);
				}
			 
		}
		else 
		{
			newWidth = imgWdith *  (myHeight / imgHeight);
			
			if(newWidth < myWidth){
				newWidth = myWidth;
				newHeight = imgHeight * (myWidth / imgWdith );
				}
		}
	document.getElementById("bg").width = newWidth;
	document.getElementById("bg").height = newHeight;
 
 
 }