Loading Hilberts

Recently I thought: why are loading spinners such boring shapes, why not fill the loading space, surely CSS is capable of this? Thus was born the Loading Hilbert. Here we show a simple iterate of the Hilbert curve in a square. It is easy to imagine how we could do this for any curve, and even fill spaces dynamically with javascript if we were so inclined (this would certainly have performance constraints). I have not seen anyone else do this yet, somehow, though it is pretty straight forward to do with an SVG and CSS animations.