This interactive choropleth map lets viewers click countries to select or deselect them, dimming unselected nations and highlighting the chosen one while fading the sphere background. The map and a color legend for economic groups update together, with the legend also supporting selection. Built with D3 v5, it uses `d3.geoNaturalEarth1` and `d3.geoPath` to render GeoJSON from the World Atlas TopoJSON, while `d3.zoom` enables panning and zooming. The legend and map are composed via D3 data joins and `d3.scaleOrdinal` with a spectral color scheme.