Selection on docs website is broken

[Seasle]

🐛 Bug Report

On the website with documentation the mouse selection does not work, or rather it is not visible. I would like it to work correctly.

To Reproduce

Just open the website (except for the Introduction page) and try to highlight something. Had a quick look at the cause, and the --scalar-selection-background and --scalar-selection-color variables are missing on ::selection.

[Seasle]

Originally found this on a website on react-i18next and decided on the main website to check it out. i18next/react-i18next-gitbook#149

[adrai]

will close, since there's not much we can do here