indented signature leaks indent into the result

When I write

This is typically done in two steps.

1.  Lorem ipsum:

    ```signature
    List.map_wfParam (xs : List α) (f : α → β) :
      List.map f (wfParam xs) = List.map f xs.attach.unattach
    ```

then this shows up as

This is typically done in two steps.

1.  Lorem ipsum:

    List.map_wfParam (xs : List α) (f : α → β) :
          List.map f (wfParam xs) = List.map f xs.attach.unattach

in the resulting HTML. It seems that indented signature blocks leak the indentation.

(Or should I have de-indented the content of the signature block maybe?)

Reproduce the nested, indented signature block shown in the issue and compare its rendered HTML with the displayed output. Trace how indentation is handled for signature blocks inside list items; done means the rendered signature content does not retain the extra indentation while preserving the surrounding list structure.