Reduce width on title and content for header navigation

[JuliaKirschenheuter]

• Part of [BITV] 9.1.4.10/6.2 - At a browser window width of 320 CSS pixels (or at a browser window width of 1280 CSS pixels and 400% zoom magnification), the page contents do not wrap - some information and functions are not available without users having to scroll horizontally. (1) server#36965
• buttons are placed too far away

Summary

Reduce width on title and content for header navigation. Replace text buttons with icons buttons on mobile view.

🏚️ Before	🏡 After

[szaimen]

DCO needs to be fixed...

[susnux]

Seems fine, just fix the signoff

[JuliaKirschenheuter]

/compile amend /

[artonge]

/compile amend /

[github-actions]

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