Simple concept, but executed very well! Outside of audio, my only suggestion would be to make the countdown timer more noticeable (as it is you kinda have to stop playing to see where you're at), and to do floating text for the amount of time added (again for visibility).

Really cool take on the theme and i really like the mechanic, some stretchy sound effects would definitely go a long way into making this significantly more enjoyable, as well as maybe an increase in difficulty.

Absolutely loved this! The fact that there's momentum to the resize movements after button presses makes it almost feel like a precision platformer in the later levels. Very good work! 

Cool concept! I scored 495 on my second try. Some triangles can get pretty flat and really fiddly.