An interactive React visualization renders a single circle that directly follows the mouse cursor across an SVG canvas. The app uses React 16.9 hooks, specifically `useState` and `useCallback`, to track the mouse position via the SVG `onMouseMove` event handler. The circle’s center coordinates update reactively with each pointer movement, while the viewport dimensions are fixed at 960 by 500 pixels. The rendering approach relies solely on React’s declarative SVG element creation, without any external data source or animation library.