spoopy #ff8000
I saw the cover image from https://www.jezebel.com/its-time-to-submit-your-scary-stories and ran with it.
I played with the script I posted in https://merveilles.town/@alderwick/117343095032928319 but it has a flaw: the background is largely bluish which became orange too. So I preprocessed each pixel, scaling up the red and green values and setting the saturation to zero if it was below the ~95th percentile.