Fix: cybertopia themes render correctly in shadow DOM

[hbgl]

Changes

The cybertopia themes used the :root selector to define CSS variables for theming. The :root selector does not work when inside a shadow DOM. To fix the issue I changed the selector :root to :root, :host to make it work in both light and shadow DOM.

Checklist

• Markup tests, because the change only related to theming
• Updated the changelog at CHANGES.md

[github-actions]

Build Size Report

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

7 files changed

Total change +9 B

View Changes

file	base	pr	diff
es/core.min.js	8.19 KB	8.19 KB	-3 B
es/highlight.min.js	8.19 KB	8.19 KB	-3 B
highlight.min.js	8.23 KB	8.23 KB	-3 B
styles/cybertopia-cherry.min.css	548 B	552 B	+4 B
styles/cybertopia-dimmer.min.css	565 B	570 B	+5 B
styles/cybertopia-icecap.min.css	551 B	556 B	+5 B
styles/cybertopia-saturated.min.css	567 B	571 B	+4 B