This scatter plot visualizes the Iris dataset, mapping petal length on the x-axis and sepal length on the y-axis. It loads the CSV data via `d3.csv`, parses numeric fields, and uses `d3.scaleLinear` with `d3.extent` to set domains. Circles are rendered using SVG and a data join (`selectAll`, `join`), with axes added via `d3.axisLeft` and `d3.axisBottom`. The plot fills the browser window, and tick labels are styled with CSS.