Hello @DonP4 ,
The font of the RSVP block will be based on the default fonts chosen in your email's Design tab (lefthand menu):
Fonts > Article Heading affects the font of the RSVP block's title.
Fonts > Body Text affects the font of the Date, Location, and Description bits.
Buttons > Text affects the font of the reservation buttons.
The coloring aspects of the Fonts and Buttons subtabs will allow you to control the coloring of your RSVP block.
If you're worried about this affecting other aspects of your email, such as the rest of the body or your other headings, you can still change the fonts and coloring of these individually, to overwrite the default for that specific chunk of text.
See also:
Adding RSVP blocks to emails
Formatting and styling default text in emails
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