content: import PropTypes from 'prop-types';
  import React, { Component } from 'react';
  
  export default class App extends Component {
    static contextTypes = {
      router: PropTypes.object.isRequired
    };
  
    static propTypes = {
      children: PropTypes.object.isRequired,
    };
  
    render() {
      return (
        <app>
          <main className="main-frame">{this.props.children}</main>
        </app>
      );
    }
  }
  