A yellow circle with black stroke and a simple mouth follows the mouse cursor in this interactive SVG sketch. The face is composed from reusable React components—BackgroundCircle, Eyes, and Mouth—within a FaceContainer that translates the coordinate system to the cursor position. React's `useState` and `useCallback` handle mouse movement events on the SVG element, while D3's `arc` API constructs the mouth path. The code demonstrates a declarative, component-based approach to building interactive data visualizations with React and D3.