Pick a pairing for the whole deck. The first font sets headlines, the second sets everything else.
Four colors run the whole deck: the slides, the pens, the arrows and the camera border.
Whichever you pick, share the slide window in Zoom, never your whole screen. Then nothing else you do can appear on the webinar.
Set these once before the event. They drive the seats counter, the link card and the buyer moment.
This cannot be undone from here.