A world map rendered with a dark sphere and graticule grid, with landmasses in dark blue and country borders as faint strokes. Circles sized by population are overlaid at city coordinates using the natural Earth projection. The visualization uses React with D3 v5, specifically `geoNaturalEarth1` and `geoPath`, with SVG rendering. City data comes from a CSV of world cities, while country boundaries load from the world-atlas TopoJSON dataset.