function blanket_size(popUpDivVar, halfheight) {
	if (typeof window.innerWidth != 'undefined') {
		viewportheight = window.innerHeight;
	}
	else {
		viewportheight = document.documentElement.clientHeight;
	}
	if ((viewportheight > document.body.parentNode.scrollHeight) && (viewportheight > document.body.parentNode.clientHeight)) {
		blanket_height = viewportheight;
	}
	else {
		if (document.body.parentNode.clientHeight > document.body.parentNode.scrollHeight) {
			blanket_height = document.body.parentNode.clientHeight;
		}
		else {
			blanket_height = document.body.parentNode.scrollHeight;
		}
	}
	var blanket = document.getElementById('blanket');
	blanket.style.height = blanket_height+'px';
	var popUpDiv = document.getElementById(popUpDivVar);
	popUpDiv_height = '300';//blanket_height/2-halfheight; //half popup's height
	popUpDiv.style.top = popUpDiv_height+'px';
}
function window_pos(popUpDivVar, halfwidth) {
	if (typeof window.innerWidth != 'undefined') {
		viewportwidth = window.innerHeight;
	}
	else {
		viewportwidth = document.documentElement.clientHeight;
	}
	if ((viewportwidth > document.body.parentNode.scrollWidth) && (viewportwidth > document.body.parentNode.clientWidth)) {
		window_width = viewportwidth;
	}
	else {
		if (document.body.parentNode.clientWidth > document.body.parentNode.scrollWidth) {
			window_width = document.body.parentNode.clientWidth;
		}
		else {
			window_width = document.body.parentNode.scrollWidth;
		}
	}
	var popUpDiv = document.getElementById(popUpDivVar);
	window_width = window_width/2-halfwidth; //half popup's width
	popUpDiv.style.left = window_width+'px';
}
function openPopup(windowname, halfwidth, halfheight) {
	blanket_size(windowname, halfheight);
	window_pos(windowname, halfwidth);
	document.getElementById('blanket').style.display = 'block';
	document.getElementById(windowname).style.display = 'block';
}
function closePopup(popup) {
	document.getElementById(popup).style.display = 'none';
	document.getElementById('blanket').style.display = 'none';
}