Removing Splash Image?

Hey everybody. Sorry if this is really obvious, I’m quite new to the world of WordPress (actually, new to just about anything to do with websites), and I downloaded this zeeSynergie theme. It was clean, and I really like it.

I tried a few others, and everything was customizable from the splash images to the background colors and so on. This theme seems to be pretty good about it too, but there’s a splash image that has a green monster on it (right in the center of the screen, I’m sure you know what I’m talking about) and I just can’t seem to remove or change it. I tried the logo and everything, but nothing replaced the splash image, and a picture of a green monster with some fish just doesn’t fit the sleek, professional look I’m going for.

I’d love to keep using this theme. I hope that the splash image is removable. And again, sorry if it’s a really obvious answer, I’m really not good at this sort of stuff. I’m a writer, not a coder.

Thanks!