function FontSize(_size, _targets, _exceptions) {
	this.size = _size || 1.0;
	this.min = 0.9;
	this.max = 1.5;
	this.targets = _targets || ['mitte','head'];
	this.exceptions = _exceptions || 'haferbrei#hirsebrei#';
	this.lucky = this.checkBrowser();
}
FontSize.prototype = {
larger : function() {
	this.size=(this.size < this.max) ? 0.1+this.size : this.size;
	if (this.lucky) this.scale();
},
smaller : function() {
	this.size=(this.size > this.min) ? this.size-0.1 : this.size;
	if (this.lucky) this.scale();
},
scale : function() {
	var oTarget = null;
	for (var k = 0; k < this.targets.length; k++) {
		oTarget = document.getElementById(this.targets[k]);
		if (oTarget) this.changeSize(oTarget);  
	}
},
changeSize : function(oo) {
	if (oo.style) {
		oo.style.fontSize = this.size + 'em';
		oo.style.lineHeight = '1.3em';
	}
	for (var k = 0; k < oo.childNodes.length; k++) if (this.exceptions.indexOf((oo.childNodes[k].id || '#') + '#') == -1) this.changeSize(oo.childNodes[k]);
},
checkBrowser : function() {
	if (document.all && document.getElementById) return true;
	if (navigator.userAgent.indexOf('Netscape6/') >= 0 || navigator.userAgent.indexOf('Gecko') >= 0) return true;
	return false;
},
inc : function(oo) {
	this.larger();
	if (oo) oo.blur();
	return false;
},
dec : function(oo) {
	this.smaller();
	if (oo) oo.blur();
	return false;	
}
}
font_size = new FontSize();