You can customize the general font sizes.
Prerequisite
You have created your own modification set.
You have the Portal administrator function privilege.
Procedure
Click Application launcher >
Administration. The Administration opens with the
Configuration view.
Click Portal > Manage configuration sets. All available configuration and modification sets are displayed. You can edit the modification sets.
Click Edit in the row of the relevant modification set.
Click User interface.
Click Show advanced settings.
Scroll down to Font sizes.
Customize the font sizes for the different text sizes.
You have customized the font sizes in general.