function incrSize(){
	action(14, 15, 15);
	setActiveClass(2);
}
function resetSize(){
	action(12, 14, 14);
	setActiveClass(1);
}
function decrSize(){
	action(11, 12, 12);
	setActiveClass(0);
}
function action(bodySize, h2Size, h3Size){
	bodySize	= bodySize.toString()+"px";
	h2Size		= h2Size.toString()+"px";
	h3Size		= h3Size.toString()+"px";
	
	document.body.style.fontSize = bodySize;
	
	var h2s = document.getElementsByTagName("h2");
	var h3s = document.getElementsByTagName("h3");
	
	for(var i=0; i<h2s.length; i++){
		h2s[i].style.fontSize = h2Size;
	}
	for(var i=0; i<h3s.length; i++){
		h3s[i].style.fontSize = h3Size;
	}
}
function setActiveClass(elNum){
	var chUl	= document.getElementById("change-fonts");
	var chUlLis = chUl.getElementsByTagName("li");
	for(var i=0; i<chUlLis.length; i++){
		chUlLis[i].className = "";
	}
	chUlLis[elNum].className = "active";
}