This example demonstrates a minimal D3.js visualization: a solid yellow circle with a black outline centered on an SVG canvas. The circle fills the full height of the 960x500 pixel viewport, positioned via a translated group element. The code imports the `select` and `arc` functions from D3 v5, though only `select` is used to manipulate the SVG. Rendering is done entirely with SVG primitives, with styling defined in an external CSS file that imports the Ubuntu font and sets the page background. The visualization serves as a basic template for testing VizHub’s editing environment.