function sfoglia(id, foto1, foto2) {
	src = $(id).src;
	if(src.indexOf(foto1) > -1) {
		$(id).src = '/img/gallery/documentazione/big/'+foto2;
	} else {
		$(id).src = '/img/gallery/documentazione/big/'+foto1;
	}
	
	Effect.Fade(id, {
		from: 0, to: 1
	});
	
}

function folder (id) {	
	img = $(id+'-folder').style.backgroundImage;
	if(img.indexOf('folder_open') > 1) {
		$(id+'-folder').style.backgroundImage = 'url(/img/folder.png)';
	} else {
		$(id+'-folder').style.backgroundImage = 'url(/img/folder_open.png)';
	}
	
	Effect.toggle(id, 'blind');
}