This example draws a simple smiley face entirely with SVG shapes: a yellow circle for the head, two black circles for the eyes, and an arc for the mouth. The layout is computed from the SVG’s width and height attributes, with fixed constants for eye spacing and altitude. It uses D3 v7’s `select` and `arc` helpers, applying `attr` to position each element and `path` with an arc generator to define the mouth’s curved geometry.