how to change scrollbar slider color in a theme

Running Debian 11 and xfce, I'm trying to figure out how to change the default scrollbar slider colors, the dull grey just doesn't do it for me. Edit: Ok, this works: scrollbar { -XfceTasklist-min-button-length: 3000; /* Needed or else no buttons! */ -GtkScrollbar-has-backward-stepper: true; -GtkScrollbar-has-forward-stepper: true; } scrollbar slider { min-width: 20px; } scrollbar button {padding: 6px} /* dark green: pointer is not in the active window */ scrollbar slider:backdrop { background-color: #00aa00; } scrollbar button:backdrop { color: #00aa00; } /* green: pointer is in the active window but not on the slider/button */ scrollbar slider { background-color: #00ff00; } scrollbar button { color: #00ff00; } /* dark red: pointer is hovering over slider/button, but mouse button not pressed */ scrollbar slider:hover { background-color: #aa0000; } scrollbar button:hover { color: #aa0000; } /* red: slider/button is active */ scrollbar slider:hover:active { background-color: #ff0000; } scrollbar button:active { color: #ff0000; } /* slider maxed out, window active */ scrollbar button:disabled { color: white; } /* slider maxed out, window inactive */ scrollbar button:backdrop:disabled { color: white; } /* What is this? */ scrollbar button:checked { color: black; } ... any comments or improvements most welcome.