var originalFontSize = 1;
var currentFontSize = 1;

function changeFontSize(sizeDifference) {
    currentFontSize = currentFontSize + (sizeDifference * 0.1);
	if(currentFontSize > 1.4){
		currentFontSize = 1.4;
	}else if(currentFontSize < 0.5){
		currentFontSize = 0.5;
	}
	setFontSize(currentFontSize);
}

function resetFontSize() {
	currentFontSize = originalFontSize;
	setFontSize(currentFontSize);
}

function setFontSize(currentFontsize) {
    fs = currentFontSize + "em";
	var stObj = document.getElementById("wrapper");
	stObj.style.fontSize = fs;
}