I thought it was a really creative and well executed one button idea! A lot of people tried to find ways to either work around the limitation (by allowing you to use mouse input + a button) or shoehorn single button controls into a genre that usually requires more. You made a whole new game type that only requires a single button and I thought it was quite clever. I loved all the little animations too.
criticisms:
1. as others mentioned 5 minutes is too long
2. give easy another gate
3. allow keyboard input. I know that's technically more than one button, but I think if it has the exact same functionality it still counts. hovering my mouse over that button for 5 minutes sucks, and caused me to miss 5 seconds away from the end q_q
4 stars!