A single gray circle tracks the mouse cursor across an SVG canvas, shifting its center position in real time to follow pointer movement. The React component manages the cursor coordinates through the `useState` hook, updating the circle's `cx` and `cy` attributes whenever the SVG's `onMouseMove` event fires. Rendered with ReactDOM, the visualization uses a fixed 960×500 viewport and a circle radius of 30 pixels, demonstrating simple state-driven interaction within a declarative UI framework.