Stylized Bar Chart
This bar chart displays the top 10 most populous countries in 2020, with country names on the vertical axis and population counts on the horizontal axis. Built with React and D3 v5, it uses `d3.scaleBand` for the categorical y-axis and `d3.scaleLinear` with a maximum domain for the quantitative x-axis. SVG rect elements render the bars, and D3’s `format` function converts tick labels into abbreviated units (e.g., "1.4B"). Data comes from the United Nations World Population Prospects 2019, loaded asynchronously via `d3.csv`.