Thank you for your feedback, I will be adding more levels. The goal is to have somewhere between 50-100 levels at least. About the pause, I was thinking about it but it kind of can be used as cheating, to pause the game and figure out the answer you know :)
I think the game is pretty good. You kept it small and organized, without bugs and problems. I like that you implemented achievements, though I dont think that you need graphics settings here, as there is no mayor difference in quality.
Thank you for the feedback :). You are right about the graphics, the difference, both visual and in performance, is unnoticeable. Like pretty much everything else in the game I did it mostly to get experience for future games.
Thanks! I was really nervous about the style