A multi-line chart displays cumulative COVID-19 death totals over time for each country, using a logarithmic y-axis to accommodate disparate magnitudes. A Voronoi overlay, computed with `d3.Delaunay`, maps the nearest data point to mouse coordinates, so hovering highlights that country's trajectory in black. The visualization uses React, D3 v5's `scaleTime` and `scaleLog`, and renders SVG paths from the Johns Hopkins CSSE dataset.