Customizing Axes
This bar chart displays the population of the top 10 most populous countries, using 2018 estimates from the United Nations World Population Prospects. It demonstrates how to customize D3 axes by removing the y-axis domain line, adding grid lines with a custom tick size, and formatting x-axis tick labels to abbreviate values in billions. The chart uses D3 v5’s `scaleLinear`, `scaleBand`, `axisBottom`, and `axisLeft` APIs, rendering to SVG with custom styling for ticks, labels, and the title.