scrollbar-color-active sets the color of the scrollbar when the thumb is being dragged.
The GIF above has reduced quality to make it easier to load in the documentation.
Try running the example yourself with
textual run docs/examples/styles/scrollbars2.py.
from textual.app import App from textual.widgets import Label TEXT = """I must not fear. Fear is the mind-killer. Fear is the little-death that brings total obliteration. I will face my fear. I will permit it to pass over me and through me. And when it has gone past, I will turn the inner eye to see its path. Where the fear has gone there will be nothing. Only I will remain. """ class Scrollbar2App(App): def compose(self): yield Label(TEXT * 10) app = Scrollbar2App(css_path="scrollbars2.css")