Map Data
A world map rendered with a natural Earth projection displays global city populations as scaled golden circles, with landmasses in dark tones and graticules overlaid. The visualization uses React with D3 v5, including `d3.geoNaturalEarth1` and `d3.geoPath` to draw the map from TopoJSON world-atlas data, while city coordinates and population sizes come from a CSV loaded via `d3.csv` and mapped through `scaleSqrt`. The SVG output layers spheres, land, country borders, graticules, and city circles, with opacity creating a subtle glow effect.