Habpanel theme changes

i have openHAB2 running on a debian server and since some days im testig also openhabian on a RP3.
i noticed that the theme on the RP3 for HABpanel looks a bit different. for example the font size on the PR3 is larger.

is there a particular reason for that? where could i find the corresponding files to change/amend the HABpanel themes?
i like to have all set to the same as on my server setup.

thanks a lot in advance