Still Point
Inspired by the great design of a Rachel Hauser quilt called Still Point in the Turning World. http://www.stitchedincolor.com/2016/04/a-still-point-in-turning-world-quilt.html
I loved the myriad symmetries and the different regions you can see as fundamental. c & d control the color in HSV mode. c is kind of a starting color, and then d is the difference in hues.