This interactive scatter plot visualizes COVID-19 total cases over time for nine countries, with each country represented by a distinct color. Hovering over a legend item highlights that country’s data points while fading all others. The visualization is built with React and D3 v5, using `scaleTime`, `scaleLinear`, and `scaleOrdinal` for axes and color mapping. The data comes from the JHU COVID-19 dataset loaded via `d3.csv`, rendered as SVG circles with hover-driven opacity changes through React state.