This example visualizes the Iris dataset as a scatterplot, mapping petal length along the x-axis and sepal length along the y-axis. Points are colored by species through CSS classes, with setosa in yellow, versicolor in red, and virginica in pink. The visualization uses D3 v7 APIs including `csv` for data loading, `scaleLinear` for scaling, `axisLeft` and `axisBottom` for axes, and SVG circles rendered by `selectAll().data().join()`. The chart fills the browser window and is built with a React-friendly plain JavaScript approach.