This example renders a world map using the geoNaturalEarth1 projection from D3, displaying countries as green SVG paths with black outlines. The code fetches country boundaries from the world-atlas dataset via the `json` function, extracts features using the `topojson` library's `feature` method, and projects them with `d3.geoPath`. The visualization employs simple CSS styling for the country shapes against a light blue background.