window.addEvent('domready', function(){
changesize();
});
window.addEvent('resize', function(){
changesize();
}); 
function changesize(){
		wH = getHeight();
		wW = getWidth();
		var bg = document.getElementById('bgimg');
		var ratio = 1.497076023392;
		testthis = wH * ratio;
		if (wH * ratio < wW) { bgNewW = wW +'px'; bgNewH = Math.round(wW / ratio) +'px'; } else { bgNewH = wH +'px'; bgNewW = Math.round(wH * ratio) +'px'; }
		bg.style.width=bgNewW;
		bg.style.height=bgNewH;
}