Why won’t this work?

Question

why won’t the JS in this code work?
https://code.sololearn.com/WmB29DFQFYR0/?ref=app

Answer 1

In html, every value passed to the loadNext function should be in single quotes, loadNext('#one', '#two')

In js should use document.querySelector instead document.getElementById

x should display 'block' and e should display 'none'

Missing fifth child background color in css
https://code.sololearn.com/W58eXorJ60zf/?ref=app

Answer 2

Defying Gravity
Are you wanna this?
https://code.sololearn.com/WaNTR6LvGZ7l/?ref=app

Answer 3

You can't pass the element through their id selector.