To change the font family for your Headings or Body content, you can go to Appearance → Mediavine Trellis → Display, then select an option from the Body Font or Heading Font dropdown under the Font Sizes & Typefaces heading.
Any font available from Google fonts can easily be added to your Trellis theme as a custom font, though we strongly recommend choosing a Web Safe font for best performance. Web Safe fonts might not be fun, but they're fast and reader-friendly.
The Body Font selection will be applied to all other text elements, including paragraphs, navigation, and article meta (categories and tags).
The Heading Font selection will be applied to H1, H2, H3, H4, H5 and H6 headings. This includes widget titles, which are wrapped in H3 tags.
After you change the setting, click Save in the upper right corner of the Display Settings, then view a post to ensure that the desired font is now displayed.
If the desired font is not displayed, clear the Page CSS from Manage Trellis JS/CSS options in the admin bar, and clear any other caching plugins you might be using.