This example demonstrates a bare-bones JavaScript keyboard interaction test, where the page’s body listens for `keydown` events and logs each pressed key’s value to the browser console. The rendering is minimal, using a CSS class for large centered text but no visual output beyond the console log. The code relies on the native DOM `EventListener` API on `document.body` and the `console.log` method, with no external libraries or frameworks. The interaction is limited to keyboard input, with no data source or chart rendering involved.