Hi! Ahmed,
I hope you are well and good. I am working on this project. I am randomly checking developer's work, whom I am following, to get inspiration and you are one of them.
Well I am not here to give feedback intentionally but, I would like to introduce an error in your work. I find that
when I keep on pressing 9 like until I display 999,999,999,999,999
as if I one more click button 9 then it converts to 10,000,000,000,000,000 (<---- This)
If I move on enter a large number, then after a certain point (when display filled with number) then your data overflow from display.
I know you are talented and have enough experience of web development and you will update your code once you will have free time.
With Regards Aakash Verma