Tailwind css 3.0.5 classes is not working with react

Question

Tailwind css 3.0.5 is not working with react. I have installed tailwind css as per the official installation guide of the tailwind css (https://tailwindcss.com/docs/guides/create-react-app). The code which, I have written is below.

package.json

{
  "name": "react-complete-guide",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "@testing-library/jest-dom": "^5.11.6",
    "@testing-library/react": "^11.2.2",
    "@testing-library/user-event": "^12.5.0",
    "react": "^17.0.1",
    "react-dom": "^17.0.1",
    "react-scripts": "4.0.1",
    "web-vitals": "^0.2.4"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build",
    "test": "react-scripts test",
    "eject": "react-scripts eject"
  },
  "eslintConfig": {
    "extends": [
      "react-app",
      "react-app/jest"
    ]
  },
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  },
  "devDependencies": {
    "autoprefixer": "^10.4.0",
    "postcss": "^8.4.5",
    "tailwindcss": "^3.0.7"
  }
}

src/index.css

@tailwind base;
@tailwind components;
@tailwind utilities;

postcss.config.js

module.exports = {
  plugins: {
    tailwindcss: {},
    autoprefixer: {},
  },
}

tailwind.config.js

module.exports = {
  content: [
    "./src/**/*.{js,jsx,ts,tsx}",
  ],
  theme: {
    extend: {},
  },
  plugins: [],
}

src/app.js

import "./index.css";

function App() {
  return (
    <h1 className="text-3xl font-bold underline">
      Hello world!
    </h1>
  );
}

export default App;

Answer 1

I think you need to update your create-react-app version, you're using version 4 which need something like Craco to let you override the PostCSS configuration natively

Try to update your create-react-app globally with this command npm install -g create-react-app, then try this step again https://tailwindcss.com/docs/guides/create-react-app

OR

Update your create-react-app only on current project npm install react-scripts@latest