This interactive scatter plot visualizes the Iris dataset, mapping petal length against sepal width, with each point colored by species. Hovering over a species in the color legend highlights only points of that species by increasing their opacity while dimming others. The visualization uses React with D3 scales, including `d3.scaleLinear` for axes and `d3.scaleOrdinal` for colors. It fetches data via `d3.csv` and renders all marks and the legend as SVG circles.