function hide_thankyous(evt) {
    $$('.thankyou-letter').each(function (letter) {
        letter.setStyle('display', 'none');
    });
}

function show_thankyou(image) {
    return function(evt) {
        evt.stop();
        if(image.getStyle('display') == 'none') {
            image.setStyle('display', 'block');
        }
        else {
            image.setStyle('display', 'none');
        }
    }
}

function bind_thanks() {
    $$('.thankyou').each(function (thankyou) {
        var src = thankyou.getProperty('letter');
        var wrapper = new Element('div', {'class': 'thankyou-letter'});
        var image = new Element('img', {'src': src});
        wrapper.grab(image);
        thankyou.grab(wrapper);
        thankyou.addEvent('click', show_thankyou(wrapper));
    });

    window.addEvent('click', hide_thankyous);
}

window.addEvent('domready', bind_thanks);