Sometime around the turn of the 20th century, Dutch painter Piet Mondrian started working with stark lines and geometric shapes in bold, high-contrast colours, a form of abstract art he called Neo-Plasticism — and what we now know colloquially as colour-blocking. The art world was never the same... and neither was fashion, for that matter. Who could forget Yves Saint Laurent's iconic 1965 collection featuring shift dresses directly inspired by some of the artist's tableaus?