content: import React from 'react';
  import Header from './header';
  
  const Layout = ({content = () => null }) => (
    <div>
      <Header />
  
      <main className="app-layout">
        {content()}
      </main>
  
      <footer className="site-footer">
        <small>基于<a href='https://github.com/kadirahq/mantra'>Mantra</a> &amp; Meteor构建.</small>
      </footer>
    </div>
  );
  
  export default Layout;
  