There are many ways to style your website. They can roughly be grouped into three styling approaches — standard CSS, CSS Modules, and CSS-in-JS — all of which Gatsby supports.
Gatsby doesn’t have an opinion about which styling approach you choose. Almost every possible option is supported through official and community plugins.
Gatsby has rich built-in support for standard CSS tools and can be easily extended through plugins.
How to load local font files into your site.
How to load fonts from Google Fonts and Typekit.