text: import React,{Component} from 'react'
  import ReactDOM from 'react-dom'
  import {
    render,
    BrowserRouter as Router,
    Route,
    Link
  } from 'react-router-dom'
  import { AppContainer } from 'react-hot-loader';
  import Header from 'component/header/header.jsx';
  
  const App = () => (
    <Router>
      <div>
        <Header></Header>
        <h2>Official Site</h2>
        <ul>
          <li><Link to="/client/">Home</Link></li>
          <li><Link to="/client/product">Product</Link></li>
          <li><Link to="/client/about">About</Link></li>
        </ul>
        <Route path="/client/:id?" component={Child}/>
      </div>
    </Router>
  );
  
  const Child = ({ match }) => (
    <div>
      <h3>ID: {match.params.id}</h3>
    </div>
  );
  const Client = () => {
    return EASY_ENV_IS_DEV ? <AppContainer><App /></AppContainer> : <App />;
  };
  ReactDOM.render(<Client />, document.getElementById('app'));
  
  
  