This example shows a React application that renders the text “Hello Reaaact!” centered on the page, using a large font size. The app is built with React and ReactDOM, with the main component defined as a simple functional component returning a div with a CSS class. The code uses React 16.13.1 from a UMD build via unpkg, and renders the component into the DOM element with the id "root". The styling is applied through an inline CSS rule that sets the font size to 13em.