Reply To: Grey Border Box around EPUB

I was confused because you said it was an EPUB file… but you cannot embed an EPUB in HTML (that I know of). What you have in your example is a “Publish Online” document. I don’t think there is any way to remove that gray area. You might be able to adjust the position of their html inside the iframe, though. You would use CSS to set the position of the content inside the iframe and the size of the iframe.