Why it's not working for me?

Question

can u please give a brief about it

Answer 1

https://code.sololearn.com/WQRK8k2In7st/?ref=app.
Can you tell me what I'm saying is right or not?
*first I want to type the intro part and save as intro.css
*then type the main code and use the id attribute to call the intro part...
Is this the right procedure or whether i want to use the style tag??

Answer 2

https://www.w3schools.com/css/default.asp

Answer 3

If you want, you can post a link to the code that is not working and we would help you find the problem.