What are layers?

Basically layers are just 'layers' on the webpage. Each layer can sit on top of or below another, they can change their position, the layering order, and still remain independant from other layers or the main page (but they can be related as well, if that's what you want). I know you can do these and more in other ways, but I prefer layers. Here's a demo down below on some of the things that I like to use layers for, disappearing and bouncing.
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