var  currentSize = 100;

function setFontSize(ev, percentage, prevent)
{
    if (document.getElementsByTagName) {
	currentSize = percentage;
	tbheight = currentSize * 1.25 - 100
	if (tbheight < 0) {
		tbheight = 0};
	document.getElementsByTagName("body")[0].style.fontSize = currentSize + '%';
	document.getElementById("expander").style.height = (tbheight) + 'px';
	}
}


function decreaseFontSize(ev)
{
    setFontSize(ev, currentSize / 1.13, true);
}


function defaultFontSize(ev)
{
    setFontSize(ev, 100, true);
}


function increaseFontSize(ev)
{
    setFontSize(ev, currentSize * 1.13, true);
	
}