Let's make a map with D3.js!
A choropleth-style world map displays countries as light green polygons on a blue sphere, with thin black borders, using D3.js v5 and TopoJSON. The example loads world-atlas geographic data from unpkg, converts TopoJSON to GeoJSON via the `feature` function, and renders the map with `d3.geoPath` and a Natural Earth projection (`geoNaturalEarth1`). The SVG canvas includes a background sphere path and country paths, demonstrating a minimal, clean approach to geographic visualization with accessible web libraries.