This example displays a world map using a Natural Earth projection, showing country boundaries and graticule lines over a light gray sphere. The visualization loads geographic data from a TopoJSON file using `d3.json`, then converts it to GeoJSON features and interiors with `topojson.feature` and `topojson.mesh`. React renders the map as SVG paths computed by `d3.geoNaturalEarth1` and `d3.geoPath`, with styling applied through CSS classes for the sphere, graticule, and country fills.