If you click an illustration, a variety of styles will appear in the top menu.
There is currently 5 different styles (from silhouette to realistic).
You can additionally change the color of 3 of them (silhouette, wireframe and grayscale). We selected some harmonic color presets to save you time and allow a better result , when combined.
This youtube video shows you how to do: https://www.youtube.com/watch?v=WHiAx1dCc9Q