delete libs for bundling and minimizing Css

package.json

@@ -73,19 +73,15 @@
     "@types/styled-system__theme-get": "^5.0.1",
     "babel-loader": "^8.2.2",
     "chromatic": "^5.9.2",
-    "cssnano": "^5.0.12",
     "eslint-plugin-prettier": "^4.0.0",
     "file-loader": "^6.2.0",
     "husky": "^6.0.0",
     "lint-staged": "^11.0.0",
     "npm-run-all": "^4.1.5",
-    "postcss": "^8.4.4",
-    "postcss-cssnext": "^3.1.1",
     "react": "^17.0.2",
     "react-dom": "^17.0.2",
     "react-is": "^17.0.2",
     "rollup-plugin-peer-deps-external": "^2.2.4",
-    "rollup-plugin-postcss": "^4.0.2",
     "run-s": "^0.0.0",
     "size-limit": "^4.12.0",
     "tsdx": "^0.14.1",

tsdx.config.js

@@ -1,18 +1,10 @@
 const svgr = require('@svgr/rollup').default
 const peerDepsExternal = require('rollup-plugin-peer-deps-external')
-const postcss = require('rollup-plugin-postcss')
-const cssnext = require('postcss-cssnext')
-const cssnano = require('cssnano')
 
 module.exports = {
   rollup(config, options) {
     config.plugins = [
       peerDepsExternal(),
-      postcss({
-        plugins: [cssnext({ warnForDuplicates: false }), cssnano()],
-        extensions: ['.css'],
-        minimize: true,
-      }),
       svgr({ ref: true }),
       ...config.plugins,
     ]