This example displays a bar chart of salary by country, with bars colored according to a categorical "Purchased" field. Built with the Vega-Lite API, it registers the vega, vega-lite, and vega-tooltip libraries, then fetches CSV data via `d3.csv` and renders the visualization into the full browser window. The chart uses bar mark sizing, field encodings for x, y, color, and tooltip, and applies a custom configuration for axis styles and typography.