A line chart displays cumulative COVID-19 deaths over time for multiple countries, with each thin gray line representing a country's trajectory. Hovering over any point activates a Voronoi overlay, highlighting the corresponding country's line in blue and displaying a label with its name, death count, and date. The visualization uses React for component structure, D3 v5 scales and line generators, and d3-delaunay's Voronoi diagram for hit-testing. Data comes from the CSSE COVID-19 global time series, rendered as SVG with logarithmic y-axis scaling.