This choropleth map colors countries by economic classification using an ordinal color scale with the spectral scheme, sourced from the World Atlas TopoJSON dataset. The map supports interactive zooming and panning, and clicking a legend item highlights matching countries while dimming others. It is built with D3 v5, using `d3.geoNaturalEarth1` and `d3.geoPath` for geographic projections, and `d3.zoom` for navigation, with all elements rendered as SVG.