Let's Make a Face with D3.js
A yellow circle with a black outline forms a face on a red background. Two black circles serve as eyes, positioned symmetrically using width and height calculations. The example demonstrates basic SVG shape creation with D3.js v6, using the `d3.select` and `d3.append` methods to add circles with attributes like `cx`, `cy`, and `r` to an SVG element. The code shows how to set fill colors and stroke properties directly in D3.