Is it possible to add background images to form headers?

Specifically, something like what I've accomplished in the the attached screenshot, but without me forcing a conventional image over with negative margin. 

Put another way, rather than a form-wide background image, I'd rather have a background image that fits in my header. 

I may have found a workaround to achieve the requirements you showed us in your screenshot. Please see the steps below.

1. Add the image as the logo of your form.

2. Set the Dimensions of the logo to 700px by 350px.

3. Inject the following CSS codes to your form.

.form-all:before {

    position: initial !important;

}

.form-all {

    margin-top: initial !important;

}

How-to-Inject-Custom-CSS-Codes

4. Delete the Image added to your form.

Here's a cloned version of your form where I have applied the steps mentioned above.

https://form.jotform.com/92136133706957

I hope this helps. If, in any case, I have misunderstood your concern, please feel free to let us know and give us more details.

Thanks! I'll take a look!