Help! Basic Theme changer is not working

Question

So I took a basic java script class and tried to made this theme toggler but it isn't working properly nothing happens when I click the button
Kindly suggest improvements
Here is the code 😊
https://code.sololearn.com/WijXlASh0w72/?ref=app

Answer 1

For your javascript classList.toggle(“.black”) get rid of that period and make it toggle(“black”)

Answer 2

It was showing some kind of error

Answer 3

Thanks it works now....