Nice game, I enjoyed the sound effects a lot, added a lot to the making it feel as if I'm actually flipping cards. One thing I would change is there is a lot of UI elements without labels, for example, there is a slider in the options menu that I just had no idea what it did. That also somewhat goes for the top right counter, so if I were to make one change I would just label those to the player so it is a bit easier to understand.
Besides that, Nice Job :)