This example visualizes the Iris dataset in a 3D scatter plot, comparing sepal and petal measurements across two marker groups. The first trace plots sepal length, sepal width, and petal length, while the second trace uses petal width instead, with distinct marker styling and opacity. Built with Plotly.js via `Plotly.newPlot`, the code loads the CSV data using `d3.csv` and organizes columns into x, y, and z coordinates. The layout removes all margins to maximize the plotting area, and the chart renders inside a designated `div` element.