Able to add class name / new styles to a image on a Collection page

I am wanting to add a unique class name to an image that is bound to a collection. As you will see in my read-only link below I have 7 pages being built from a Members Collection Page. Each page is pulling in a unique “background” image. My goal would be to be able to apply a unique object-position property to each image. I have tried adding a unique class to the image on each page but it ties the properties to the “image 18” class. Even if I add an image not bound to a collection, I am still unable to apply a unique class.

Any help would be much appreciated.

Here is my read-only link –

Here is my site Read-Only: LINK
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