A grid of 100 identical yellow smiley faces fills the viewport, each rendered as a small SVG via React components. The code draws a yellow circle with a black stroke, two black eyes, and an arc-based mouth using `d3.arc`. Each face is positioned by a `FaceContainer` that translates the SVG group to the center of a 100 by 100 viewBox. The React app maps over `range(100)` from d3 to create the repeating layout, with all styling and geometry hard-coded.