This website uses resources from a variety of places. Here's a list of them:

• Icons made by Freepik from www.flaticon.com is licensed by CC 3.0 BY
• Free vector art from www.Vecteezy.com
• Puzzles inspiration from Mindful Me 101 Awesome Puzzles by Hinkler
• Puzzles inspiration from Lovatts magazines
• Puzzles inspiration from Puzzler magazines