managed to complete the game, surprisingly, though I'm guessing full 3-stars are required for the secret levels and that's not happening. some observations:

- there don't seem to be any hotkeys, esc to bring up the pause menu, and for undo and reset.

- it'd be great if the timer only started after the first move, not as soon as 'go!' disappears.

- the last tutorial said collecting stars would unlock more levels, but you unlock the next one and nothing else when you complete the current one, for no matter how many stars. I think at least 3 levels should be available at any given time to still allow progress if you managed to get stuck on a level, though simply completing them isn't that big of a deal and you can always go back to earlier ones.

- turbo mode is kinda weird. time limits are the same but blocks move faster, what was the reasoning behind it? not that I can get 3 stars even on tutorial or easy levels with it, but it's more of a personal shortcoming.

- and I just noticed undo counts as a move, so the second star is not that easy either even if you ignore the timer.

- because of the angle, sometimes it's not always clearly visible where the goal is (not to mention when blocks cover it). some sort of highlighting would be good to have.