Site template to use for inset page content over background image?

Site URL: http://annelydia.com

Per a client's request, I am trying to modify / create a site that has all the content inset into a white box over a full background image like this one - https://www.digsdesignco.com

Are there any templates that do this?

Thanks for any advice! 

Turns out the 7.0 template "Greenwich" allows for inset but now I'm looking for code I can inject to the header to use a full bleed background image. 

This is not doing the trick:

body {
 background-image: url("paper.gif");
 background-color: transparent !important;
}

The site you posted is made using the Squarespace Julia Template.

These templates allow for sitewide background images without any code,  

• Adirondack
• Avenue
• Aviator - The info page also supports a page-specific background image
• Five
• Forte
• Momentum
• Montauk
• Native

Here is the Avenue demo site and you can remove the name avenue and replace it with any of the above to see the template. I am an Avenue user and have used full bleed background images in the past. 

https://avenue-demo.squarespace.com/blog-avenue

Here is the julia demo:

https://julia-demo.squarespace.com/

Julia will work because it is a member of the Montauk family of templates. Here is the guide to add a site wide background image. 

https://support.squarespace.com/hc/en-us/articles/205812788

If you wish to use the Greenwich template this code should work in custom css after uploading image to file manager and capturing the full url of its location.