This example displays cumulative global COVID-19 deaths over time for multiple countries using a log-scaled line chart. Hovering over any line reveals a tooltip with the country name, death count, and date, while the active line is highlighted. The chart uses React with d3.v5’s `scaleTime`, `scaleLog`, and `line` generators, and implements a Voronoi overlay via `d3.Delaunay.from` and `voronoi.renderCell` to capture mouse events across the SVG. Data comes from the CSSE COVID-19 global time-series dataset, loaded with `d3.csv`.