I’ll give you an example:
My index is in MainProject folder. It has a resources folder, that contains an images folder and a css folder.
From my css, to get into the the images I need to go one folder back and type in the url, so that would be:
If we change the scenario: My index is in MainProject folder. It has a resources folder and an images folder, my css folder is inside the resources folder.
Now I would have to go 2 directories back
More importantly, to look at what the issue is, inspect element is vital. You can click on the element that you’re targeting in the html, and then click the image link. It will tell you the path it tried if it failed, and it’s pretty easy to adjust from there: