This example displays a bar chart of the top 10 most populous countries in 2018, using data from the United Nations World Population Prospects. The chart customizes D3 axes by removing default domain lines and tick lines, applying a custom tick format that converts G to B for billions, and styling tick labels, axis labels, and the title via CSS. It uses `d3.scaleLinear` and `d3.scaleBand` to map population and country names, with `d3.axisBottom` and `d3.axisLeft` to render the axes.