A React component renders an SVG circle that follows the mouse pointer across a 960×500 canvas. The SVG’s `onMouseMove` event updates React state via `useState`, and `useCallback` memoizes the handler to prevent unnecessary re-renders. The circle’s `cx` and `cy` coordinates are bound to the current mouse position, demonstrating a reactive, declarative drawing interaction. Unlike D3, this example relies solely on React’s state management and SVG’s native event handling to create a live, mouse-driven visualization.