/**
* Variables
*/
var maxSize = 64;
var minSize = 32;
var initialSize = minSize;
var growSpeed = 5;

function growThumb(thumbnail) {
	checkSize(thumbnail);
	thumbnail.targetSize = maxSize;
	changeSize(thumbnail);
} 

function shrinkThumb(thumbnail) {
	checkSize(thumbnail);
	thumbnail.targetSize = minSize;
	changeSize(thumbnail);
} 

function changeSize(thumbnail) {
	if(thumbnail.currentSize > thumbnail.targetSize) {
		thumbnail.currentSize -= 1;
		setTimeout(function(){changeSize(thumbnail);},growSpeed);
	}
	else if(thumbnail.currentSize < thumbnail.targetSize) {
		thumbnail.currentSize += 1;
		setTimeout(function(){changeSize(thumbnail);},growSpeed);	
	}
	thumbnail.style.width = thumbnail.currentSize + "px";
	thumbnail.style.height = thumbnail.currentSize + "px";
}

function checkSize(thumbnail) {
	if(thumbnail.currentSize == null) {
		thumbnail.currentSize = initialSize;
	}
}