Mean Green Calculator Feedback

Thanks for any feedback or suggestions. The CE ‘step back’ key caused me a lot of problems.
I obviously need to be a lot more tidy and concise with my JS. It really seems I made things
ugly and overly complicated. Happy coding.

it mean and its green thats for sure. overall its really good. i dig the slight button animation that is done well. the different tones of green give it a nice modern look.

why does it go to three decimal places with whole numbers??
just curious