In marmota.app, Markdown-blockquotes can be used not only to render blockquotes, but also to create general-purpose blocks:
> A "normal" blockquote
>{render-as=author} A general-purpose block with the
> CSS-class box-author
The second blockquote in the example above is a general-purpose block. Whether this block will be rendered in some special way is determined by the presentation design of your presentation.