This example shows a yellow smiley face centered on a responsive full-screen SVG. It uses React (via the `react` and `react-dom` production UMD builds) to declaratively render three circles: a large yellow face with a black stroke, and two smaller eye circles positioned symmetrically from the center. The face radius is derived from the window height minus half the stroke width, while the eyes use fixed offsets and radius. The code configures dimensions and offsets as JavaScript constants, then translates the SVG group to the screen’s center.