Front end colour picker?

I am looking to achieve something very basic, but I don’t know if it is possible. I would like to display a filled circle on on a black backround. The colour of the circle’s fill should preferably be determined by a colour picker available on the front end, but I could also live with having to input a hex value directly as input.

Anyone know if this is possible or have any idea how to achieve it?

Maybe it could be possible to generate automated pages based on a url format value)?

Here is my site Read-Only: LINK
(how to share your site Read-Only link)

you could have a range of divs with different colors and when the user clicks one the background is changed through an interaction

probably some custom widget out there too