Why the background color isn't changing.

Question

See the 474 line of js, why the background color is not changing.
See the code↓↓
https://code.sololearn.com/WkuUg3mobwCA/?ref=app

Answer 1

You are changing the style of the body.So you have to write the .style also which you are missing.
Like that:
changeBodyBackgroundColor.style.backgroundColor = "grey";
After that ,if you call the openSetting() function it will work.