Animation with javscript and a vertical sprite of animation frames.

sprite-animation.js

Today.page_turn_forward = function () {
    var y = 322,
        i = 0,
        frame_count = 27,
        frame = $('.anim-frame'),
        interval;

    frame.show()

    // Start position
    frame.css('background-position', '0 ' + (y * frame_count * -1) + 'px');

    interval = setInterval(function() {
        i++;
        frame.css('background-position', '0 ' + (y * (frame_count - i) * -1) + 'px');

        if ( i == frame_count ) {
            clearInterval(interval);
            frame.hide();
        }
    }, 1000/30);
};