Styling fixes (graphql#4249)

Checked for broken styles and fixed them and also went over the links by
using linkinator. I did check a lot of tools but looks like there isn't
a good way at the moment to check for broken links that is maintained.

Resolves graphql#4242

Author: JoviDeCroock

cspell.yml

@@ -110,6 +110,7 @@ words:
   - Nextra
   - headlessui
   - Fastify
+  - tailwindcss
   - svgr
   - ruru