Can't Find Code That Changed Background Image

I put some code into my Store in an attempt to change the background of my product page to a specific image. This code did have the unintended effect of changing the whole site's default background. I made some more unrelated changes and went back to find the code some weeks later. However, now I can't seem to find this code anywhere. I thought I put it into Store Page>Settings>Advanced>Page Header Code Injection, not there. Looked on several other pages' settings for Page Header Code Injection, nothing. Looked at the Website Tools under Custom CSS and Code Injection, nothing there either. I'm at a loss, I just want to remove this code.

This was the post that I believe I got the code from to change the background of the shop, if that helps: 

54 minutes ago, somedayfarms said:

I put some code into my Store in an attempt to change the background of my product page to a specific image. This code did have the unintended effect of changing the whole site's default background. I made some more unrelated changes and went back to find the code some weeks later. However, now I can't seem to find this code anywhere. I thought I put it into Store Page>Settings>Advanced>Page Header Code Injection, not there. Looked on several other pages' settings for Page Header Code Injection, nothing. Looked at the Website Tools under Custom CSS and Code Injection, nothing there either. I'm at a loss, I just want to remove this code.

 

This was the post that I believe I got the code from to change the background of the shop, if that helps: 

 

Could you have placed the code into a code block on the page?