How to add admonition from obisidian to mkdocs

There's a neat trick with obsidian where you can add little expandable text boxes.

It looks like this:

> [!info]- Click to Expand Me!
> > Hello!!!

Click to Expand Me!

Hello!!!

With html, that would look something like this:

<details>
  <summary>Click to Expand Me!</summary>
  <blockquote>Hello!!!</blockquote>
</details>

By default, with mkdocs (no callouts plugin), that same Obsidian markdown syntax renders as this instead. Plain Markdown has no idea what [!info]- means, so it just falls back to a plain nested blockquote with that text sitting there literally, not styled or collapsible at all:

<blockquote>
  <p>[!info]- Click to Expand Me!</p>
  <blockquote>
    <p>Hello!!!</p>
  </blockquote>
</blockquote>

So to render the obsidian style in mkdocs, we just need to add a little plugin.

Install it (into your venv):
```
venv/bin/pip install mkdocs-callouts
```

Add to mkdocs.yml — the plugin plus the markdown extensions the output relies on:

plugins:
  - search
  - callouts          # converts Obsidian > [!note] → Material admonition

markdown_extensions:
  - admonition        # renders the callout boxes
  - pymdownx.details  # needed for collapsible callouts
  - pymdownx.superfences

With that in place, the exact same Obsidian syntax at the top of this page renders as the real, styled, collapsible box.