text: import React, {PropTypes} from 'react';
  import { Link, IndexLink } from 'react-router';
  import styles from './style.css';
  
  const Sidebar = () => {
      return (
          <nav>
              <div>
                  <ul>
                      <li>
                          <IndexLink to="/" activeClassName="active">Home</IndexLink>
                      </li>
                      <li>
                          <Link to="/courses" activeClassName="active">Courses</Link>
                      </li>
                      <li>
                          <Link to="/about" activeClassName="active">About</Link>
                      </li>
                  </ul>
              </div>
          </nav>
      );
  };
  
  export default Sidebar;