An interactive choropleth map encodes a country's economy category through a spectral color scale. Pan and zoom via D3's `zoom` and `event` APIs manipulate the SVG projection, while clicking a legend tick highlights only countries in that category. Hovering reveals the country name and value via a `title` element. The map uses `d3.geoPath` and `geoNaturalEarth1` on World Atlas TopoJSON, with the legend built from `scaleOrdinal` and `schemeSpectral`.