11219 adapt UI font size (#12042)

* Migrate all CSS files to the Base.css

* fixed seprator and toggle button misalignment

* deleted the original css files and updated the css references

* Apply requested changes

* Add selectors to avoid styling errors

* Remove superfluous calls to class.getResource

* Extract and adapt hardcoded styles from ai chat

* Simplify ai gdpr dialog

* Remove unused hardcoded padding

* Adapt JournalInfo

* Fixed review notes

* CHANGELOG.md

* more CHANGELOG.md

* fix dark text color

* CHANGELOG.md

---------

Co-authored-by: Christoph <[email protected]>
Co-authored-by: Carl Christian Snethlage <[email protected]>

CHANGELOG.md

@@ -83,7 +83,6 @@ Note that this project **does not** adhere to [Semantic Versioning](https://semv
 - We disabled the actions "Open Terminal here" and "Reveal in file explorer" for unsaved libraries. [#11920](https://github.com/JabRef/jabref/issues/11920)
 - JabRef now opens the corresponding directory in the library properties when "Browse" is clicked. [#12223](https://github.com/JabRef/jabref/pull/12223)
 
-
 ### Fixed
 
 - We fixed an issue where certain actions were not disabled when no libraries were open. [#11923](https://github.com/JabRef/jabref/issues/11923)
@@ -126,6 +125,7 @@ Note that this project **does not** adhere to [Semantic Versioning](https://semv
 - We fixed an issue when the preview was out of sync. [#9172](https://github.com/JabRef/jabref/issues/9172)
 - We fixed an issue where identifier paste couldn't work with Unicode REPLACEMENT CHARACTER. [#11986](https://github.com/JabRef/jabref/issues/11986)
 - We fixed an issue when click on entry at "Check Integrity" wasn't properly focusing the entry and field. [#11997](https://github.com/JabRef/jabref/issues/11997)
+- We fixed an issue with the ui not scaling when changing the font size [#11219](https://github.com/JabRef/jabref/issues/11219)
 
 ### Removed