Map hover
This example demonstrates interactive hover behavior on a map of Canada, where moving the mouse over a province highlights it by changing its fill color and triggers a tooltip displaying the province name. The tooltip, a positioned HTML div, appears near the cursor, shows the region’s name, and hides on mouseout. Built with D3 v7, it uses `d3.geoAlbers` for projection, `d3.geoPath` for rendering GeoJSON features, and CSS classes to manage visibility and styling.