Here is my calculator: https://codepen.io/jmarkell/full/Ldoxvr/
I think I caught most of the errors, but I am sure I missed some. Let me know if you can break it.
I want to figure out how to get the keypad working with each button on the calculator, but I am not quite sure how to go about binding events for click and keyboard efficiently. And I have determined I really suck at design and picking color schemes.
Well anyway, any feedback you can provide will be greatly appreciated. Thanks for taking a look!
Edit: This link is now updated to the fixed site.