content: import React, { Component } from 'react';
  import { render } from 'react-dom';
  // import ReactDOM from 'react-dom';
  import { Router, Route, Link, IndexRoute } from 'react-router';
  import createBrowserHistory from 'history/lib/createBrowserHistory';
  
  import About from './About';
  import Home from './Home';
  import Repos from './Repos';
  import RepoDetails from './RepoDetails';
  import ServerError from './ServerError';
  
  class App extends Component {
    render() {
      return (
        <div>
          <header>App</header>
          <menu>
            <ul>
              <li><Link to="/about" activeClassName="active">About</Link></li>
              <li><Link to="/repos" activeClassName="active">Repos</Link></li>
            </ul>
          </menu>
          {this.props.children}
        </div>
      )
    }
  }
  
  render((
    <Router history={createBrowserHistory()}>
      <Route path="/" component={App}>
        <IndexRoute component={Home} />
        <Route path="about" component={About} title="About Us"/>
        <Route path="repos" component={Repos}>
          <Route path="/repo/:repo_name" component={RepoDetails} />
        </Route>
        <Route path="error" component={ServerError} />
      </Route>
    </Router>
  ), document.getElementById('root'));
  