This choropleth map displays world countries colored by economy category, with an accompanying ordinal color legend. Clicking a legend category filters the map by fading non-matching countries to low opacity and highlighting the selected group. Built with D3 v5, it uses `geoNaturalEarth1` and `geoPath` for projection, `scaleOrdinal` with `schemeSpectral` for colors, and `zoom` for panning. Data comes from the World Atlas TopoJSON and TSV files, rendered as SVG paths.