* chore(docs): document HTML custom templates
Shows an example of custom template.
TODO:
- [ ] finish documentating;
- [ ] add possibility to pass `-cargs` to Manim Slides' `convert` method when calling the Sphinx extension.
Closes#356
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* chore(docs): document changes and fix
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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
