This example shows a choropleth map of U.S. states colored by the logarithm of their seven-day average positive COVID-19 test counts, with tooltips revealing state names, death averages, and positive test averages. Built with D3 v6 and TopoJSON, it uses `d3.geoAlbersUsa` for projection, `d3.geoPath` to render state boundaries, and `d3.scaleOrdinal` with the `schemeOrRd` color scheme. Data comes from a CSV file linked in the code, and the map is rendered as SVG with hover effects that change state fill colors.