This example visualizes the relationship between fuel efficiency (miles per gallon), horsepower, weight, and country of origin for cars from the UCI Auto MPG dataset, loaded via a CSV from a GitHub Gist. It uses a scatter plot with circles sized by weight and colored by origin, rendered through the Vega-Lite API and Vega-Lite’s declarative specification. The code registers Vega and Vega-Lite with `vl.register`, configures axes and tooltips via `vega-tooltip`, and sets the visualization to fit the browser window. Data is fetched asynchronously using `d3.csv`.