How to make the circle empty (Transparent) inside?

Question

I want to make the circle transparent from the inside. Look at my code, it's a rounded figure with colored borders. How to remove its inner part, that could there be something to insert?
https://code.sololearn.com/WZerUu3UKKRY/?ref=app

Answer 1

You can!
background: transparent;

Answer 2

blue write the version of the code for him with transparency

Answer 3

you cannot make it transparent from the inside

Answer 4

No need, I understand. I know how to do that