This example demonstrates a simple sunrise and sunset animation using a yellow circle that moves vertically within an SVG canvas. The circle alternates between two positions—descending to the bottom and rising to the top—via a CSS `@keyframes` rule named `sunrise-sunset`, applied with an infinite alternate timing function. The markup also includes a static SVG circle and a brief demonstration of D3 version 7's `select` function to insert text into the body. The animation runs in a 500x500 viewport, showing basic CSS-driven motion without JavaScript interaction or external data.