function fixHeight(one,two) {
	if (document.getElementById(one)) {
		
		var lh=document.getElementById(one).offsetHeight;
		var nh = Math.max(lh)-480;
		if (nh >= document.getElementById(two).offsetHeight) {
			document.getElementById(two).style.height=nh+"px";
		}
	}
}

window.onload=function(){
	fixHeight('nav','contentWrapper');
}