Why the size of border does not change when I change the value of margin?

Question

https://code.sololearn.com/Weg1ZcH5sA1x/?ref=app

Answer 1

In your code, there is two weird symbols in front of margin. Looks like periods, but unable to copy/paste them, so no idea what that is. Just remove them and it works fine.

https://code.sololearn.com/W2PNY056YF3s/#html

^Working.

Answer 2

weird..what is that ?😁😁Thanks for your help!

Answer 3

I think... the code has problem cuz come from w3 school... this one too... Don't no why.😅
https://code.sololearn.com/WWXA8gvS58N9/?ref=app