[TOMT] PBS kids AD from childhood

So when I was younger at night, from what I can recall (for me) PBS kids would show a ad that the screen was full black and then would show flashing colors/lights (looked like chalk/paint to me) and it went across the screen and it had ambient music. (I loved this ad so much when it came on)

I’ve been trying to find it for years, hopefully someone here knows what I’m talking about please help.