Is it possible to get the script from this site?

At the top of this site has the letter "A" when clicked, the user can choose the font, font size, and color of the background image
Is it possible to get this script or maybe there's a ready-made solution for integration on your website?
Found the script from this site on github, but it is unlikely it will work out GitbookIO cms, and to decouple the script alone my knowledge has not yet been possible.
March 20th 20 at 11:51
1 answer
March 20th 20 at 11:53
So there is no big deal, it's regular css. You write the styles you need, assign them to classes. And then the buttons do. When pressed, take the class and assign it for example <body>. All this can be seen in the browser console, under elements, on the proposed page.

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