A little review for this little game.

Notes:

1. This is the first game I see that offers control binding! Nice touch. :) By the way, I see you used QWERTY-only programming instead of a layout-independent one (as many games did, unfortunately!!), but it is possible to do so. Still, your settings menu largely solves this issue. :) My AZERTY shakes your hand with a firm grip!
2. Wow, simple yet effective concept! It does work; starting, I was afraid it would be too complicated, but I realize you can visualise the die as two orthogonal rolling cycles, which makes it workable. :) (By the way, I had a similar issue in my game, and I realized in hindsight that showing the smooth transition of the faces could have greatly help players feel the rotations; I think this idea also applies to your game.
   I think the difficulty balance is nice! The time given is neither too long nor too short.
3. One case that is not entirely clear to me is when the game asks for two opposite sides (such as 1 and 6, for example); I merely put one of the two (eg 6), and it was considered as correct.
   [Ah, important note: I realize the concept is not exactly what I thought: I imagined you had to match both the higher and lower target sides by having the right upper and middle faces, but as it turns out, the higher indicator is in fact what comes next (Tetris-style), and you only need to match the lower indicator… So, the game is a bit easier than I thought; yet, the concept is still close.]
   I am also not sure about what yellow means (for one of the target sides), since it disappears after some time and does not seem to make a difference.
   [I realize this may have been to show which is the current target side.]
4. The pixelated style is simple but clear. Some sounds would have been a nice addition.

I think it is a nice minigame, that makes use of the structure of a die for spatial visualisation. Effective!

it would be cooler if the control was inverted by default