This scatter plot visualizes the Iris dataset, comparing sepal length and width across three species. The code uses D3's `scaleLinear`, `scaleOrdinal`, `axisBottom`, and `axisLeft` to construct the chart, with points styled via CSS classes. Interactive legend items trigger hover states that adjust point opacity. Data loads from a CSV via D3's `csv` parser, and a `ResizeObserver` handles responsive sizing.