An interactive line chart shows cumulative COVID-19 deaths over time for each country, using data from the Johns Hopkins Coronavirus Dataset. A Voronoi overlay, built with `d3.Delaunay` and `d3.voronoi`, maps every pixel to the nearest data point, enabling hover to highlight the corresponding country’s line and display a tooltip with the death count and date. The chart uses a logarithmic y-scale (`d3.scaleLog`) and renders as SVG via React, with axes generated by `d3.axisBottom` and `d3.axisLeft`.