You can change the font sizes with adding to any element `.text-*` e.g. (`.text-sm`).
-`.text-xs` (0.75rem)
-`.text-sm` (0.875rem)
-`.text-md` (1rem)
-`.text-lg` (1.25rem)
-`.text-xl` (2rem)
> ##### Tip!
> You can also add `.text-sm` to `body`, with this you get a complete smaller font on the UI or can you add `.text-sm` to `.main-sidebar` or `.main-header` & `.brand-link`.