Theming blocks in Panels Does anyone know of a module or some other way to allow users to customize blocks or panes (or even regions) in a panel on their profile page (i.e.: the authenticated user could change the color background of the block, or add a picture to the background, could change the color of the borders and font, etc?)

That means the same blocks could be themed differently by all users.

Ideally each block / pane would have a tab with some kind of a drop-down allowing the user to select options to add HTML and CSS on a per block basis.

The site uses Bartik (D7.)

Any feedback on this would be greatly appreciated. :)
Just some ideas:

I use the Fieldable Panels Panes a lot on smaller web page to add direct content to the Panel pane instead of having to create content for it first. FPP are entities. Maybe you can use for a user to add images (and text, files, etc.) to their profile page? Honestly, I've only used it on site building level.

I know about this module Classy Panel styles, but never used it. Maybe you can also set the permissions that users can use the pre-defined styles.

There is also a widget type module (as used in Atrium) where a user can move blocks (Panel panes) around. I don't have a link for that.