This example uses D3 v7 to create an animated, generative visualization of circles. It displays a dynamic sine-wave pattern where 10 to 15 circles move vertically and change radius over time, rendered as SVG elements on a full-window canvas. The animation runs at a 60 FPS interval, with each frame updating the `cx`, `cy`, and `r` attributes of the circles via `selectAll` and `.join`. The periodic motion is computed using `Math.sin` for both position and size, creating a smooth, evolving sine-wave composition.