Fonts / Colors / Site-Wide Styles
To change the fonts, primary colors, or make other style changes that affect your entire site (and not just a particular post or page), go to Appearance > Customize > [Theme Name] Options. From there, you can find tons of options for changing your colors to changing your menu layout.
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If you’re using Bubble Tea or Honey Glow and want to replace the script font with a custom one, follow the tutorial here.