Ah, I was just confused by terminology ;-). By screen we usually mean an HTML page of the site. I've edited "notification screen" to "notification email" to make this issue clear now :).
Lots of fiddling later, and I have the CSS rendering properly. We didn't have these fancy emails in v9, and it was pushing some assumptions prebaked into the mail and notification frameworks. It all flows through well now.
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#2271 - Notification email issues
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