docs: switch sphinx theme to shibuya

[hwhsu1231]

Changes

Switch sphinx theme to shibuya.

Checklist

• Added markup tests, or they don't apply here because...
• Updated the changelog at CHANGES.md

[github-actions]

Build Size Report

Changes to minified artifacts in /build, after gzip compression.

3 files changed

Total change -3 B

View Changes

file	base	pr	diff
es/core.min.js	8.19 KB	8.19 KB	-1 B
es/highlight.min.js	8.19 KB	8.19 KB	-1 B
highlight.min.js	8.23 KB	8.23 KB	-1 B

[joshgoebel]

Please attach the screen snaps of what it would look like.

[hwhsu1231]

Please attach the screen snaps of what it would look like.

Sure. The following are the screenshots in dark and light modes:

[joshgoebel]

Docs for the theme: https://shibuya.lepture.com/writing/lists/

@allejo any thoughts here? I didn't really have any issues with the existing docs, but...

[arturict]

Small suggestion: if this docs theme change is purely visual, could you mention expected rendering impact or rollback path in the description for easier review?

[hwhsu1231]

@arturict The main reason I suggested switching the Sphinx theme from RTD to Shibuya (as mentioned in #4420) comes down to two key design features: "dark mode" and the "three-column layout":

Finally, I plan to submit a new PR later to migrate the current highlight.js documentation theme from sphinx-rtd-theme to shibuya, which offers a built-in "dark mode", and its "three-column layout" (global TOC, page content, local TOC) aligns perfectly with modern theme trends. Below is a preview of what it looks like after migrating to Shibuya:

[joshgoebel]

I'll let @allejo decide this one. I'm not sure a dark theme is critical and I don't often change things just because they are newer/shinier... when who knows what problems come with new things... but this seems ok... just waiting for allejo to weigh in.