The Kitchen Sink app implements styling on the slider that I can't replicate. I've read the docs component: slider and don't understand what to do. Is there documentation that better explains all the options?

- How did they implement the thumb border on drag?
- How do I change the color of trackFilled and thumb when dragging?

I'll happily do any reading if I just know where/what to read to understand. Please show me where to look? What am I not understanding?

Deepest gratitude!