Hello HTML
This example renders a smiling face using SVG shapes drawn with React components, featuring a large yellow circle for the head and two smaller black circles for eyes. The code imports the `arc` function from d3 but does not use it, focusing instead on React’s declarative JSX to position elements with fixed numeric coordinates. It demonstrates a minimal integration of React 18 and d3 v7 in a single HTML page, using ReactDOM to mount the SVG into the root div. The visualization is static, with no interaction or data binding.