const List = () => {
  return (
    <ul>
      <li>這是列表</li>
    </ul>
  )
}

const App = () => {
  return (
    <div>
      <h1>Hello React</h1>
      <List/>
    </div>
  )
}

const root = ReactDOM.createRoot(document.querySelector('#root'));
root.render(<App />);