Good question. That would require to modify the theme or even creating a new one.
Maybe I will do this in the future, because I don't like how and how hard it is to add custom HTML in markdown with Hugo. This seems to be a lot easier with vitepress.
On the other hand I don't have the need to add more custom elements, so hugo is okay for now. Also not a fan of migrating just for the migrations sake. :)
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