This example shows a D3.js area chart displaying Happiness Scores across countries on a categorical x-axis. The visualization uses an SVG rendering approach with `d3.area` to draw a steelblue filled region beneath the score line. It loads CSV data from a GitHub gist via `d3.csv`, applies `d3.scaleBand` and `d3.scaleLinear` for positioning, and annotates axes with labels using `d3.axisBottom` and `d3.axisLeft`.