jQuery code doesn't work, Why?

Question

I can run this on computer using Notepad.
I copy this code to sololearn , It doesn't work.
why?
https://code.sololearn.com/WcLX7IJr2wT1/?ref=app

Answer 1

You should add the jQuery link at the HTML head tag and remove the <script> tags in the JS section.

https://code.sololearn.com/WLSPdT2a70g9/?ref=app

Answer 2

Perfect answer，thankyou@Jonathan Pizarra