Add ayu-highlight.css

[Cldfire]

Follow-up to #1221.

I began putting a theme together and thought "hmm, I feel like I've done this before." Turns out... I did! https://github.com/rust-lang/mdBook/blob/master/src/theme/ayu-highlight.css

I copied that CSS into static/ayu-highlight.css and added an exception for it to the .gitignore; if there's a better way to include it, let me know.

Here's what it looks like:

Note that a nice, easy way to see what it looks like for a large variety of input is to go to https://highlightjs.org/static/demo/ and replace the default stylesheet with the contents of whatever theme you'd like to test:

Example

[jyn514]

I copied that CSS into static/ayu-highlight.css and added an exception for it to the .gitignore; if there's a better way to include it, let me know.

I think that's fine; ideally it would get upstreamed to highlight.js but since it's a single CSS file maintaining it in tree doesn't seem like a burden. Doing fancy git things with subtrees or submodules doesn't seem worth it (and you'd have to have a repo for a single file, which also seems silly).

This looks really good in source mode, which was pretty lacking before. Great job!

Before:

After:

The one thing I would change is that I think you made /// dark green for rustdoc - could you add the same color here?

[Cldfire]

ideally it would get upstreamed to highlight.js

I agree, that would be neat to do someday. First the theme would need some cleanup and modernization; ayu has changed in the years since I made it for mdbook.

The one thing I would change is that I think you made /// dark green for rustdoc - could you add the same color here?

Unfortunately I don't believe I can. highlight.js doesn't differentiate between doc comments and normal comments when highlighting rust code; they both get the hljs-comment class. This means they have to share a style.

[jyn514]

Oh, that's unfortunate :( ok, this is still great then :)