Slider styling

[j-fu]

The idea comes from an example by Márk Munkácsi, see https://dev.to/munkacsimark/styled-range-input-a-way-out-of-range-input-nightmare-jeo It was public on Codepen, so it is MIT licensed. Should fit with the Unlicense as MIT is not GPL...

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[j-fu]

I found the blue chrome default a bit annoying...