Where to get started with Dark Mode

Question
1

Hi! I understand that Sparkle may have an option to add a button to switch a website to Dark Mode. Where can I find this? Thanks!

2

There isn’t much on it but if you go to this link - https://youtube.com/watch?v=gw5nK-3EXS0 (from Sparkle Docs page) and start the video around 6min 50sec an outline of how to use Dark Mode is talked about…