Mudanças entre as edições de "Exemplo de componente React"

import React, { Component } from 'react';
import './css/pure-min.css';
import './css/side-menu.css';
 
class App extends Component {
  render() {
    return (
<div id="layout">
 
    <a href="#menu" id="menuLink" className="menu-link">
 
        <span></span>
    </a>
 
    <div id="menu">
        <div className="pure-menu">
            <a className="pure-menu-heading" href="#">Company</a>
 
            <ul className="pure-menu-list">
                <li className="pure-menu-item"><a href="#" className="pure-menu-link">Home</a></li>
                <li className="pure-menu-item"><a href="#" className="pure-menu-link">Autor</a></li>
                <li className="pure-menu-item"><a href="#" className="pure-menu-link">Livro</a></li>
 
 
            </ul>
        </div>
    </div>
 
        <div id="main">
            <div className="header">
              <h1>Cadastro de Autores</h1>
            </div>
            <div className="content" id="content">
              <div className="pure-form pure-form-aligned">
                <form className="pure-form pure-form-aligned">
                  <div className="pure-control-group">
                    <label htmlFor="nome">Nome</label> 
                    <input id="nome" type="text" name="nome" value=""  />                  
                  </div>
                  <div className="pure-control-group">
                    <label htmlFor="email">Email</label> 
                    <input id="email" type="email" name="email" value=""  />                  
                  </div>
                  <div className="pure-control-group">
                    <label htmlFor="senha">Senha</label> 
                    <input id="senha" type="password" name="senha"  />                                      
                  </div>
                  <div className="pure-control-group">                                  
                    <label></label> 
                    <button type="submit" className="pure-button pure-button-primary">Gravar</button>                                    
                  </div>
                </form>             
 
              </div>  
              <div>            
                <table className="pure-table">
                  <thead>
                    <tr>
                      <th>Nome</th>
                      <th>email</th>
                    </tr>
                  </thead>
                  <tbody>
                    <tr>
                      <td>Alberto</td>                
                      <td>alberto.souza@caelum.com.br</td>                
                    </tr>
                  </tbody>
                </table> 
              </div>             
            </div>
          </div>            
 
 
</div>     
    );
  }
}
 
export default App;