Changing The colors of a specific element with buttons

Question

So I have this code. I want to be able to change the color of the text inside the output div using buttons. anyone know how?
https://code.sololearn.com/Wa38bFrnaDrA/?ref=app

Answer 1

you can try this approach

https://code.sololearn.com/WBFDCSE4pRR3/?ref=app

Answer 2

Didn't even know about that. Thank you stranger. :)