postcss.config.js

const tailwindcss = require('tailwindcss');
const cssnano = require('cssnano')

const purgecss = require('@fullhuman/postcss-purgecss')({

    // Specify the paths to all of the template files in your project
    content: [
        "./src/**/*.html",
        "./src/**/*.js",
    ],

    // Include any special characters you're using in this regular expression
    defaultExtractor: content => content.match(/[\w-/.:]+(?<!:)/g) || []
})

module.exports = {
    plugins: [
        require('tailwindcss'),
        require('autoprefixer'),
        ...process.env.NODE_ENV === 'production'
            ? [purgecss]
            : [],
        process.env.NODE_ENV === 'production'
            ? cssnano({ preset: 'default' })
            : null,
        ...process.env.NODE_ENV === 'production'
            ? [purgecss]
            : []
    ]
}