Feature request: redesigned interface, showing more contrast

[SebastJava]

I regularly use both https://colorable.jxnblk.com and https://marijohannessen.github.io/color-contrast-checker/

The first one for the HSL sliders, and the second one for the design. Design = Function. Yes, I think it looks nice, but it is not just about looking nice, it is also more functional: it shows the contrast between the foreground and the background colors in a much better way. Colors can only be fully appreciated when there is contrast. This https://colorable.jxnblk.com only shows a full screen colored background with letters in the foreground. So this https://marijohannessen.github.io/color-contrast-checker/ is doing much better on this.

It also comes with nice features such as uppercase hex values and lighten on mouse over.

Quick mockup: