This choropleth map displays countries colored by economic classification using a spectral color scale. Users can click legend items to highlight all countries in that category while dimming others, with zoom and pan via `d3.zoom`. The map is rendered with `d3.geoPath` and `d3.geoNaturalEarth1` projection using TopoJSON data from the world-atlas dataset. A legend, built with custom SVG circles and text, provides interactive filtering, and hover effects change country fill colors.