This example visualizes cumulative COVID-19 deaths over time for each country, using a log-scaled y-axis to accommodate wide disparities in death tolls. Hovering over the chart highlights the corresponding country’s line and displays a tooltip with the exact date and death count. The visualization uses React for component structure and D3 v5 (d3-scale, d3-shape, d3-axis) with an SVG renderer. A d3-delaunay Voronoi overlay accelerates mouse interaction by mapping hover positions to the nearest data point. Data comes from the Johns Hopkins Coronavirus Dataset.