Greasy Fork

Faded options only have limited functionallity without signing in to the script

What does that mean? I already sign in here and added this script to favorites.

Also, I dont know how to change the background colors. From the footer.

Signing in means granting the script additional privileges. It can be done at the bottom the settings page: https://anilist.co/settings/apps

To change the background colour, select "--color-background", the site theme you are using, and pick a colour.