This scatter plot visualizes the iris dataset, showing sepal length against sepal width for three flower species, with each species colored distinctly via a custom color legend. The visualization uses D3 v5 to load CSV data and build an SVG scene, employing `scaleLinear` for the axes, `scaleOrdinal` for color encoding, and `axisBottom`/`axisLeft` to render gridlines. Semi-transparent circles reveal overlapping points, while a reusable `colorLegend` module generates a categorical legend with labeled circles and a background rectangle.