Here are two projects involving the geometrical-constructive art of Piet Mondrian, one of my preferred artists, the golden ratio and ϕ. For this purpose, I used the same color palette favored by Mondrian: yellow, red, blue, black and gray.
Mondrian meets Pythagoras and Fibonacci
In the first project, I used squares, that are proportional to each other by the golden ratio or ϕ, to prove the Pythagorean theorem as shown in the Zhoubi Suanjing (or Chou Pei Suan Ching – 周髀算經), one of the oldest Chinese mathematical texts (circa b.c. 200).