content: 
  import React, { Component } from 'react';
  import { render } from 'react-dom';
  
  
  import Child from './Child';
  
  
  // localStorage.setItem("access", false);
  
  class App extends Component {
  
    constructor() {
      super(...arguments);
      this.state = {
        route: window.location.hash.substr(1),
        access: false
      };
    }
  
    componentDidMount() {
      window.addEventListener('hashchange', () => {
        this.setState({
          route: window.location.hash.substr(1)
        });
      });
    }
  
    changeAccess(value) {
      console.log(`App: ${value}`);
      // localStorage.setItem("access", value);
      this.setState({
        access: value
      });
    }
  
    render() {
      return (
        <div className="container">
          <header>App</header>
          <menu>
            <ul>
              <li><a className="btn btn-default" href="#/">Home</a></li>
              <li style={{ display: this.state.access ? 'none' : 'inline-block' }}>
                <a className="btn btn-default" href="#/registration">Registration</a>
              </li>
              <li style={{ display: this.state.access ? 'none' : 'inline-block' }}>
                <a className="btn btn-default" href="#/login">Login</a>
              </li>
              <li style={{ display: this.state.access ? 'inline-block' : 'none' }}>
                <a className="btn btn-default" href="#/users">Users</a>
              </li>
              <li style={{ display: this.state.access ? 'inline-block' : 'none' }}>
                <button className="btn btn-default" type="button" 
                onClick={this.changeAccess.bind(this, false)}>Exit</button>
              </li>
            </ul>
          </menu>
          <Child route={this.state.route}
            access={this.state.access}
            onchangeAccess={this.changeAccess.bind(this)}
          />
        </div>
      )
    }
  }
  
  render(<App />, document.getElementById('root'));