Smiley Face Part 1
A smiling face is drawn in SVG with a large yellow circle for the head, two smaller black circles for eyes, and an incomplete mouth. The page combines static SVG markup with a React app that renders a separate "Hello JSX" heading via `ReactDOM.render`. The example uses React 17 production UMD builds and plain SVG elements like `circle` with explicit `cx`, `cy`, `r`, `fill`, and `stroke` attributes, demonstrating basic shape composition without interactive behavior.