A motorless propeller spins continuously on a grey background, its three blades and central hub rotating around the center of an SVG canvas. The blades use a red-to-black linear gradient, while the hub is a plain yellow circle. The rotation is driven by D3.js v6’s `transition.attrTween`, which interpolates the group’s `transform` attribute to increment the angle by 360 degrees per second with `d3.easeLinear`. No data source is involved; the visualization demonstrates a purely procedural animation.