fix(styles): Make sure footer with legal links is shown correctly

[susnux]

• Resolves: Fixed footer (banner) blocks view of public shares on smaller screens #36485
• Resolves: [Bug]: Public view footer broken #34399
• Resolves: Footer height in public view too small if imprint/privacy link set #34305

Summary

Fix public pages footer height. If there are legal links or a signup link or both we need different heights of the footer.
Otherwise the footer content will be clipped and overlay the app.

Adjusted colors in the screen shots to make clear what is which element:

before	after

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

[susnux]

/backport to stable29

[susnux]

/backport to stable28

[szaimen]

Looks good from the screenshots but didnt test and didnt review the code

[skjnldsv]

/compile /