build: minify css file

Author: lokesh-coder

package.json

@@ -5,7 +5,7 @@
   "main": "index.js",
   "scripts": {
     "build": "rm -rf build && NODE_ENV=production npm run build:css && webpack ---config ./config/webpack.prod.config.js",
-    "dev": "npm run watch:css && webpack-dev-server --config ./config/webpack.dev.config.js --open",
+    "dev": "npm run watch:css && webpack-dev-server --config ./config/webpack.prod.config.js --open",
     "lint": "./node_modules/.bin/eslint --ext .js,.jsx src/",
     "lint: fix": "./node_modules/.bin/eslint --ext .js,.jsx src/ --fix",
     "build:css": "postcss src/assets/css/styles.css -o src/assets/css/main.css",
@@ -44,6 +44,7 @@
     "clean-webpack-plugin": "^3.0.0",
     "copy-webpack-plugin": "^6.0.1",
     "css-loader": "^3.5.2",
+    "cssnano": "^4.1.10",
     "eslint": "^6.8.0",
     "eslint-config-airbnb": "^18.1.0",
     "eslint-plugin-import": "^2.20.2",

postcss.config.js

@@ -1,4 +1,10 @@
 const tailwindcss = require("tailwindcss");
 module.exports = {
-  plugins: [tailwindcss("./tailwind.config.js"), require("autoprefixer")],
+  plugins: [
+    tailwindcss("./tailwind.config.js"),
+    require("autoprefixer"),
+    require("cssnano")({
+      preset: "default",
+    }),
+  ],
 };