Scatterplot with Color and Interactive Color Legend
This interactive scatterplot visualizes the Iris dataset, plotting sepal width against petal length with points colored by species. The chart includes an interactive color legend; hovering over a legend entry fades non-matching points to 20% opacity and re-renders them in full opacity, allowing users to isolate a species. Built with React and D3 v7, it uses `scaleLinear` for axes, `scaleOrdinal` for colors, and custom React components for axes, marks, and the legend, rendering in SVG.