This choropleth map visualizes a small dataset of numeric values for selected countries using a dark-to-light blue-green color scale. It displays world country boundaries from the `world-atlas` TopoJSON source, rendered as SVG paths via `d3.geoPath` with a Natural Earth projection. The map uses `topojson.feature` to process countries, `d3.scaleSequential` with an `interpolateYlGnBu` scheme for coloring, and a legend built with `d3.axisBottom`. Hovering over a country reveals its ISO numeric ID and value via a tooltip, with missing data shown in gray.