This example shows a yellow smiley face built entirely with D3.js v5, featuring two eyes and a curved mouth drawn with an arc path. The face’s eyebrows, rendered as rectangles, animate up and down repeatedly over two-second intervals using chained `transition().duration()` calls. The code uses D3 selections to append SVG elements, `d3.arc` for the mouth, and attribute manipulation to position the facial features relative to the SVG's center. All rendering occurs in an inline SVG with CSS hiding page overflow.