Finished my Calculator -- still doesn't look quite right, but it works

I tried to mimic the functionality of the Canon LS-82Z calculator, just for the extra challenge and practice. You have to click the “ON” button to start using it. I just realized I forgot to make an “M” appear on the left side of the calculator screen when there is a value in memory, but the memory functions do work.

Regarding the appearance, I couldn’t figure out how to make the top 3rd of the calculator appear to be bent towards the viewer at a slight angle and still maintain a smooth appearance. That’s why the calculator appears to be flat. If anyone knows how to create that effect, I’d love to learn how that’s accomplished.

Any feedback or suggestions are appreciated. Thanks in advance!