Customizing Axis
This example shows a horizontal bar chart of the world’s most populous countries, ranking China, India, and the United States at the top by population. It uses D3 v6’s `scaleLinear`, `scaleBand`, `axisLeft`, and `axisBottom` to render the axes and bars in SVG. The x-axis uses `tickFormat` to abbreviate large numbers and `tickSize` to draw grid lines. Data loads from a CSV file and is parsed with `d3.csv`, while axis labels and a title are styled via CSS.