import React from 'react';
import ReactDOM from 'react-dom';
import Modal from 'react-modal';

const customStyles = {
  content : {
    top                   : '50%',
    left                  : '50%',
    right                 : 'auto',
    bottom                : 'auto',
    marginRight           : '-50%',
    transform             : 'translate(-50%, -50%)'
  }
};

// Make sure to bind modal to your appElement (http://reactcommunity.org/react-modal/accessibility/)
Modal.setAppElement('#yourAppElement')

function App(){
  var subtitle;
  const [modalIsOpen,setIsOpen] = React.useState(false);
  function openModal() {
    setIsOpen(true);
  }

  function afterOpenModal() {
    // references are now sync'd and can be accessed.
    subtitle.style.color = '#f00';
  }

  function closeModal(){
    setIsOpen(false);
  }

    return (
      

        Open Modal
        

          
 (subtitle = _subtitle)}>Hello
          close
          
I am a modal
          

            
            tab navigation
            stays
            inside
            the modal
          
        
      
    );
}

ReactDOM.render(, appElement);