This example combines multiple choropleth layers into a single map of the British Isles, rendered with an orthographic projection centered near the Irish Sea. It uses the `hpcc-viz` library’s `Layered` widget to stack three `TopoJSONChoropleth` layers for Great Britain, Northern Ireland, and Ireland, each at 75% opacity, over a `Graticule` layer for latitude/longitude lines. The code loads TopoJSON region data directly via the `region()` API and applies a zoom level to focus the view.