SOURCE

class Hello extends React.Component {
  render() {
    return <div>Hello {this.props.name}</div>;
  }
}

ReactDOM.render(
  <Hello name="World" />,
  document.getElementById('container')
);

<div id="container">
    <!-- This element's contents will be replaced with your component. -->
</div>

body{
  background-color: #FCFCFC;
}
.container p {
    font-size: 25px;
}