TURBO MODE. You can see in full screen. I wanted to do this project with curves different of the usual, but still using the method of Yeganeh. My fav.: 1, 7. A big thanks to @mathjp for the suggestions he gave me. Also a big thanks to @selim_tezel and to @Scratch-Minion for the projects showing Yeganeh's method and how to set transparency in colors.
Equations in the book "Le jardin des courbes" ("Garden of curves"), by Hamza Khelif. Music: Chopin - Nocturne op.9 No.2 (excerpt). Thanks to @Saftreb for the suggestion :)