Donate template hero background image shape

I’m using the Donate template.

The hero background image appears to have a wave-type shape at the bottom that I want to remove. I want the bottom to show the full image and be a straight line for the image.

I thought this could be fixed using the shape divider, but that didn’t work. I also tried to use some CSS, but that didn’t work either. I didn’t see an element for the hero image either.

How do I fix it so the hero background image has no other shape to it than the normal rectangle of the image itself?

Your help would be greatly appreciated.