Slider appearance settings

I don’t understand why I can’t create this slider
The default slider cannot make the handle a circle,
better slider is creating a beautiful slider in the demo, but it doesn’t work in practice
Has anyone solved it?

スクリーンショット 2024-04-01 072138

The ideal is the blue bar below
With the existing one, it is not possible to change the height of the bar and the height of the handle.

And this is the plugin demo page
but actually this doesn’t work