This example demonstrates how to create a smiling face using basic SVG shapes—circles for the eyes and an arc for the mouth—positioned within a 960x500 viewport. The code uses D3 v5’s `select` and `arc` functions to append elements to the SVG, while CSS styles handle page margins and a red highlighted text class. The arc is generated using inner and outer radii with a start angle of zero and an end angle of π, producing a half-circle smile centered in the composition.