Hi! Many apologies for the delayed response. The itch.io version of Abstraction in Beauty already includes Steam keys. You can find it on the game's Download page. More information on how to claim it here: https://itch.io/t/67604/how-to-get-a-steam-key-from-your-itchio-purchase
Note also that ownership of Abstraction in Beauty also discounts its price off the sequel, Plastic Reality, on Steam! You can learn more about the sequel and its powerful editing and design tools here: https://store.steampowered.com/app/1087050/Mondrian__Plastic_Reality/
Thank you for your support and thank you for playing!