So this is effectively just a random color finder, using digits of Pi as the pseudo-RNG, right? Well, guess that might be useful when trying to find a random color, lol. Definitely sounds like it made for a fun little side project.
If I may make a minor suggestion: I'd switch the position of the "min" and "max" text boxes. When specifying ranges in software, it's pretty much the norm to have minimum values on the left and maximum values on the right. It's quite unusual and unintuitive to do it the other way around, this definitely threw me off at first. The brain naturally wants to read it as "from [...] to [...]", so it's kinda weird when it says something like "from 100 to 0".
That's really the only issue I see, though. It's definitely a solid implementation for what it is. I like how the text color automatically changes to something that is still readable on whatever background color is being used.
Feel free to visit my website/blog - it's updated rarely, but it looks pretty cool!