Fork of D3 Course Code Along - Choropleth Map
This choropleth map visualizes world country income groups using a natural Earth projection, with color-coded paths representing each nation. Users can pan and zoom interactively, while a legend highlights the categorical color scale. The visualization loads TopoJSON country boundaries and TSV metadata via `Promise.all`, processes them with `d3.geoPath` and `geoNaturalEarth1`, and renders the legend with custom D3 selections and transitions.