Blazor proper collapsible sidebar suboption indentation

[yarmoliq]

Is there an existing issue for this?

• I have searched the existing issues

Is your feature request related to a problem? Please describe the problem.

Currently there is no indentation for suboptions when using collapsible sidebar. There is an example of adding indentation for child options that uses padding on the left of the options. However, this results in an indentation when sidebar is collapsed:

So you either have suboptions without indentation or a little ugly thingy :) or try to fix it by implementing a bicycle.

Describe the solution you'd like

I think the easiest and straightforward one is to just collapse category. However, I see other viable options:

1. no indentation for child options in collapsed view
2. small visible indentation in collapsed view, which results in a little bit wider collapsed sidebar (there has to be a tradeoff, right?)

Additional context

No response