For a barebones implementation this little game was really decent!
There is a little gripe with how the game handles stacking - namely, grabbed coins "choose" their slots and wait for all other grabbed coins to slot in before slotting in themselves. This slows down coin collection slightly, but is otherwise fine.
Another little issue I had at the beginning was the manual coin drop - you have to hover over the face of the coin to drop it from a stack! I did not get that for a good couple rounds, which was a frustration point.
What wasn't fine was a bug I encountered a few times, where a white coin would slot into an invalid collector (for example, red). This prevents that collector from taking up its respective coins, essentially cutting you off from a color for an entire round. Very disruptive, together with a lack of an abort round button.
Other than that, the game was fun! The coin snapping into place was tactile and the sound was satisfying. The gameplay loop was simple, but good enough for a project of this size. Had a good hour of fun, for which I thank you ;)