A world map rendered with SVG paths using D3’s `geoMercator` projection and `geoPath` generator. The code fetches country boundary data from the world-atlas TopoJSON dataset, converts it to GeoJSON via `topojson.feature`, and draws each country as a separate path element. The map fills the entire SVG viewport with no styling, showing only the raw political borders. The example demonstrates the minimal setup for geographic visualization with D3 v5.