This fork of a D3 pie chart visualizes the top 10 countries in the world for 2022, using an interactive, animated donut chart rendered as SVG. The chart segments expand on mouse hover and, upon clicking, drill down to reveal a nested second-level breakdown based on additional data attributes. Built with D3 v2 and jQuery, the visualization uses `d3.layout.pie`, `d3.svg.arc` with inner and outer radii, and `transition.attrTween` for smooth entry animations, while handling color assignments via a categorical ordinal scale.