MK Smiley face part 1
This example shows a static smiley face drawn with three SVG circles inside an HTML page. The code uses React 17 and ReactDOM to render a separate "Hello JSX" heading, while the smiley face itself is hard-coded directly in the SVG markup within the HTML body. The yellow face and two black eyes are explicitly positioned with `cx`, `cy`, and `r` attributes, and the face outline uses `stroke` and `stroke-width`. The illustration demonstrates basic SVG shape composition without any interactive or animated behavior.