Identical 60° rhombi, three to a hexagon. Each hexagon reads as a cube because the three rhombi are its three visible faces, and they’re shaded in three steps — which is how this tiling has been drawn for as long as anyone has drawn it, from Roman floors to quilts. The cubes reverse if you stare: the same drawing is a stack seen from above or a hollow seen from below.
Most people who make one of these go dark: near-black ink on black is the most-used palette on the site, because a wallpaper that recedes leaves your icons legible. It looks nothing like the bright version below — which is rather the point of being able to pick.
Any color, any size.
Free, no account. PNG or SVG.