This dashboard visualizes the relationship between fuel efficiency (MPG), horsepower, origin, and weight in a scatterplot of the Auto MPG dataset from the UCI Machine Learning Repository. Each circle is positioned by MPG and horsepower, colored by country of origin, and sized according to vehicle weight. The example uses the Vega-Lite API, registering `vega` and `vega-lite` libraries to build a declarative spec programmatically. Data is loaded via `d3.csv`, and the chart renders as an SVG with custom tooltips provided by the `vega-tooltip` handler.