content: import React from 'react';
  
  const Header = (props) => {
    return (
      <header className="header">
        <h3>Markdown Previewer</h3>
  
        <button className="small-screen-only" onClick={props.toggleMobilePreview}>{props.mobilePreview ? " Switch To Editor Mode" : " Switch To Preview Mode" }</button>
  
      </header>
    );
  }
  
  export default Header;
  