You nailed the retrogame feel with the pixel art, chiptune music and sfx. It felt like playing a NES classic. Creative take on the typical platformer and the theme too.
Quick note is that on my browser I had to zoom in to 150% to see the full game, but on 100% it looked like this. (My resolution is 1920x1080).
Maybe just mention it in the description or comments so that others know and don't give up to quickly.