function openwin( url, target, width, height )
{
	var left = ( screen.availWidth - width ) / 2;
	var top = ( screen.availHeight - height ) / 2;

	var args = 'top=' + top + ', left=' + left + 
				', height=' + height + ', width=' + width +
				', menubars=no, resizeable=yes';

	window.open( url, target, args );
	
}

var text_scale = 1;

function increaseText()
{
	text_scale += 0.2;
	document.getElementById('body').style.fontSize = text_scale + 'em';
}

function decreaseText()
{
	text_scale -= 0.2;
	document.getElementById('body').style.fontSize = text_scale + 'em';
}

function setTextSize(size)
{
	document.getElementById('body').style.fontSize = size + 'em';
}