How many lines are indented should vary depending on the font-size you set the drop cap to. But you're probably right that this CSS won't quite work on a PW with your particular font.
"Marnie," for those wondering, is the font (or a close match to the font) used for a decorative raised cap (though not a drop cap, AFAIK) in many of Amazon's advertising images. So if you want to make your book look
just like a Kindle ad...
