Fork of Choropleth Maps
This fork of a choropleth map displays the percentage of adults with a bachelor’s degree or higher across U.S. counties for 2015–19, using a purple sequential color scale. It renders an SVG map with county boundaries and state outlines via d3.geoPath, with hover effects that highlight counties by transitioning their stroke color. The visualization uses a d3.scaleThreshold for color encoding, d3.csv and d3.json for loading data, and topojson to parse geographic features. A legend with an axis shows the percentile ranges.