This example displays a simple “Hello React!” message centered on the page using a large, bold font. It demonstrates a minimal React setup by importing React and ReactDOM, defining a functional component that returns a JSX div, and rendering that component into the root element. The page loads React and ReactDOM from CDN links in the HTML, while the application logic resides in a separate bundle. Styling is applied via a CSS class defined in the document’s head, and the message scales with a 13em font size.