Making the page part, and the parts surrounding the page transparent so that the underlying image is shown through, is a feature that is not included in our product. That said, it is not impossible, but you would have to apply customisations for css and html to get this setup, and this is not something that is covered by the support agreement.
We have had this up for discussion before, but there is currently no plan to add this to our products.
Let me know if you have any other questions!
Best Regards, Maria Heij
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