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How to change a background image in theme?Asked by meckjohnson on April 28, 2015 at 02:33 PM
You should be able to do that in your Form Designer, but if it is not working we can help you with that as well.
This is the link to the video that will show you how to make the change in your Form Designer: http://www.jotform.com/form-designer/tuts/episode10/
Do let us know how it goes.