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                <div id="app"></div>


                html, body
  height: 50%
  display: flex
  flex-direction: column
  justify-content: center
  align-items: center
  font-family: Helvetica Neue
  position: relative
  top: 10px
  position: absolute
  position: absolute
  left: 120px
  top: -10px


 * A simple React component
const Hat = ({type}) => {
  let url = '';
  switch (type) {
    case 'cap': url = ``; break;
    case 'pirate': url = ``; break;
    case 'harry-potter': url = ``; break;
    case 'propeller': url = ``; break;
    case 'leprecon': url = ``; break;
  return <img src={url} className='hat' />

const thinkerImg = '';

const Thinker = () => (
  <img className="thinker" src={thinkerImg} />

const ThinkerWithHat = ({hat}) => (
  <div className="thinker-container">
    <Thinker />
    <Hat type={hat}/>

const HatSwitcher = ({onHatChanged}) => (
    Select a hat:
  <select onChange={(e) => onHatChanged(}>
    <option value="cap">Cap</option>
    <option value="pirate">Pirate</option>
    <option value="harry-potter">Harry Potter</option>
    <option value="propeller">Propeller</option>
    <option value="leprecon">Leprecon</option>

class Application extends React.Component {
  constructor(props) {
    this.state = { hat: 'cap' }
  render() {
    const onHatChanged = (hat) => {
      this.setState({ hat });
    return (
        <HatSwitcher onHatChanged={onHatChanged}/>
        <ThinkerWithHat hat={this.state.hat}/>

 * Render the above component into the div#app
ReactDOM.render(<Application />, document.getElementById('app'));