How do I get a page background file back ???

If I use the "Brick Wall Theme" and I see it has a brick wall jpg as the layout background file.  Now if I change that file to one of my files in Jotform or upload a new file - thats great.  

BUT what if I want the original brick wall file back.  It doesn't show under MY FILES so is there a way to get to the location of that file without having to select the theme all over again especially if I've made some custom functions.  I'm assuming that if I select the brick wall theme it will overwrite my customization or am I mistaken?

You may save the image in the link below so you can upload it on your form:

https://shots.jotform.com/kiran/themes/brick-wall.jpg

Thank you very much. Greatly appreciated.
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