[fcholf]

You may use xslt for this kind of operation (https://en.wikipedia.org/wiki/XSLT) but it is often overkilled. I would love a language that allows to easily write transductions of HTML documents but I think that combining simplicity and expressiveness for this kind of tasks is a bit painful. I usually end up using pandoc filters or some dedicated javascript script that transforms the DOM and output a new HTML file.