Switch to "Hugo Relearn" theme

[fritzmg]

Implements #1462

[fritzmg]

This is now ready for review.

Note: this is not a 1:1 restoration of how the docs previously looked. I deliberately only adjusted a few things from the new default theme of the new Hugo Theme, so that we can simply rely on the state of the original Theme more again.

[fritzmg]

Btw. if you are checking this out in a local repository that you had already cloned previously: switching the Git submodule is a little finicky. Something like this should work:

git fetch --all
git checkout --track origin/hugo-theme-relearn
git submodule sync
git submodule foreach git pull origin master

Though this leaves the content of the original submodule present and it will be marked as an uncommitted change.

[zoglo]

Went through a lot of pages on this version (dark mode toggle is in the sidebar anyways <3) and didn't see anything that would bother me.

I do like the new main column header from the relearn as it's not just floating anywhere.

We could improve on --INTERNAL-MAIN-BG-color as that one overwrites the normal body color - without it, it would be the same color as it is right now... but that can be fixed in a follow-up-pr imo

(And if

• the code blocks (diamond background pattern with the border)
  or anything need changes,
  that can be done in a follow-up PR <3

[fritzmg]

We could improve on --INTERNAL-MAIN-BG-color as that one overwrites the normal body color - without it, it would be the same color as it is right now... but that can be fixed in a follow-up-pr imo

Do you mean the background color of the dark mode?

the code blocks (diamond background pattern with the border)

What diamond background pattern do you mean?

[zoglo]

We could improve on --INTERNAL-MAIN-BG-color as that one overwrites the normal body color - without it, it would be the same color as it is right now... but that can be fixed in a follow-up-pr imo

Do you mean the background color of the dark mode?

Of the content in darkmode, yes. The color seems off

the code blocks (diamond background pattern with the border)

What diamond background pattern do you mean?

The second border of the code block in the old docs to make it more visible

[fritzmg]

Of the content in darkmode, yes. The color seems off

Ah yes, that is something that I actually wanted to port over from the old theme as well.

The second border of the code block in the old docs to make it more visible

Yes, but that was just the style of the original Hugo Learn theme. It was not an addition done by ourselves. I would rather keep the style of the Hugo Relearn theme. Hugo Relearn also uses Hugo's native code highlighting and not Highlight.js anymore. This is why there is now also a compeletely new color scheme for the code - I chose onedark as this one is close-ish to the atome-one-dark we had previously. I don't like the default Monokai theme.