input: |
  > [!Note]
  > Foo.
  <!-- -->
  > a
  > Bar.
  <!-- -->
  > [!Warning]
  > Baz.
output: |-
  <div class="admonition note">
    <p class="admonition-title">
      Note
    </p>
    <p>
      Foo.
    </p>
  </div>
  <!-- -->
  <blockquote>
    <p>
      a
  Bar.
    </p>
  </blockquote>
  <!-- -->
  <div class="admonition warning">
    <p class="admonition-title">
      Warning
    </p>
    <p>
      Baz.
    </p>
  </div>
