Your site uses Gatsby and Netlify CMS. Tailwind and PostCSS take care of the styling. You run gatsby develop, and encounter a cryptic error message.

Module not found: Error: Can't resolve './tailwindcss/base'

The problem is the plugin order in your gatsby-config.js file. The PostCSS plugin must appear before the Netlify CMS plugin. The correct order is as follows.

module.exports = {
  plugins: ['gatsby-plugin-postcss', 'gatsby-plugin-netlify-cms'],