This example displays an interactive world map using SVG, with countries rendered in green and the ocean as a blue sphere. It loads geographic data from the world-atlas TopoJSON file and converts it to GeoJSON using the TopoJSON `feature` method. Countries are drawn with `d3.geoPath` and the `geoEquirectangular` projection, and hovering over a country changes its fill to orange via CSS. The map uses D3 v5 for data binding and rendering.