This example demonstrates zooming and panning over a map of the United States, where clicking a state smoothly transitions the view to focus on that state’s bounding box. The visualization also supports free-form mouse or touch dragging and zooming. Built with d3.v4 and TopoJSON, it uses `d3.geoAlbersUsa` for the projection and `d3.geoPath` to render state shapes. Zoom interactions are handled via `d3.zoom` with a `d3.zoomIdentity` transform, and transitions animate the view using `zoom.transform`. The underlying GeoJSON data comes from a TopoJSON file of US states.