This example visualizes national primary balance data on a world map, using color intensity to represent each country’s economic status. Built with D3 v5, it projects geographic features via `d3.geoPath` and `geoEquirectangular`, while `scaleOrdinal` with `schemeYlOrRd` maps data values to fill colors. A custom color legend component displays the ordinal scale with circles and labels, set against a semi-transparent background. Countries render as SVG paths with hover effects, and the map supports zooming through D3’s zoom behavior. Data comes from CSV files joined to TopoJSON world geometry.