Watch: set a theme for every page
The first part of the one-different-page video: palette, font, background, and menu, then save.
The opening of One Different Page from a Preset Theme sets the look for the whole site.
Click the palette icon. Adjust the font, background color, and menu color, or choose a preset. Save and close. New pages pick up that theme.
The written steps are in Create your own color theme and Use a preset theme.