This example demonstrates a minimal React application that renders the text “Hello React!” inside a full-screen viewport. The code uses React 16.9.0 and ReactDOM to mount a functional component called `App` into a root `<div>` element. It loads the React libraries from unpkg and relies on a compiled `bundle.js` for the component logic, with global CSS removing body margins and hiding overflow. The example serves as a lightweight starter template, showing the basic structure for integrating React with a visualization environment.