webpack.config.prod.js

module.exports = {
    module: {
      rules: [
        {
          test: /\.scss$/,
          loader: "postcss-loader",
          options: {
            ident: "postcss",
            syntax: "postcss-scss",
            plugins: () => [
              require("postcss-import"),
              require("tailwindcss"),
              require("autoprefixer"),
              require("@fullhuman/postcss-purgecss")({
                // Specify the paths to all of the template files in your project
                content: [
                  "./projects/components/src/**/*.html",
                  "./projects/components/src/**/*.ts",
                  "./src/**/*.html",
                  "./src/**/*.ts"
                  // etc.
                ],
                // Include any special characters you're using in this regular expression
                defaultExtractor: content =>
                  content.match(/[A-Za-z0-9-_:/]+/g) || []
              })
            ]
          }
        }
      ]
    }
  };