Your branding is set once in the theme settings, and every page and module of the theme follows it. Open any page in the page editor and click Global theme styles in the left panel. Under Colors > Global colors the fields follow the colors of your HubSpot brand kit in order, and you can adjust each one. Under Typography you choose your fonts and the styles for body text, links and headings; Buttons and Forms are set the same way.
Click Publish changes to apply. The change reaches every page that uses the theme, so there is no need to edit stylesheets or to configure each module separately.