function getWindowHeight(){
	var windowHeight = 0;
	if (typeof(window.innerHeight) == 'number'){
		windowHeight = window.innerHeight;
	}
	else{
		if (document.documentElement && document.documentElement.clientHeight){
			windowHeight = document.documentElement.clientHeight;
		}
		else{
			if (document.body && document.body.clientHeight){
				windowHeight = document.body.clientHeight;
			}
		}
	}
	return windowHeight;
}
function getWindowWidth(){
	var windowWidth = 0;
	if (typeof(window.innerWidth) == 'number'){
		windowWidth = window.innerWidth;
	}
	else{
		if (document.documentElement && document.documentElement.clientWidth){
			windowWidth = document.documentElement.clientWidth;
		}
		else{
			if (document.body && document.body.clientWidth){
				windowWidth = document.body.clientWidth;
			}
		}
	}
	return windowWidth;
}
function setContentY(){
	if (document.getElementById){
		var windowHeight = getWindowHeight();
		var contentElement = document.getElementById('aligned');
		var contentHeight = contentElement.offsetHeight;
		contentElement.style.top = '50%';
		contentElement.style.marginTop = -(contentHeight / 2) + 'px';
	}
}
function setContentX(){
	if (document.getElementById){
		var windowWidth = getWindowWidth();
		var contentElement = document.getElementById('aligned');
		var contentWidth = contentElement.offsetWidth;
		contentElement.style.position = 'absolute';
		contentElement.style.left = '50%';
		contentElement.style.marginLeft = -(contentWidth / 2) + 'px';
	}
}
window.onload = function(){
	setContentY();
	setContentX();
}
window.onresize = function(){
	setContentY();
	setContentX();
	document.getElementById('back').style.background = 'transparent';
}