It's just opening and closing detail panes (personal recipie site), there's no reason to put the open/closed state in the url.

But if I can do it with all html, that's better than a function to add / remove a css class and document.onclick = a function to find which recipie you clicked on and adjust the css class.

Probably more useful for a nested menu. The default thing almost works out of the box. You need some css to set a proper cursor and style the clickable text properly.