Dropdown menu from a custom image

I am trying to make a custom dropdown menu, using an image. I have this code for the dropdown

Command Corners
then all the links that go in the dropdown.

The problem I’m having is that I can’t seem to get rid of the “button”, it’s grey and always slightly larger than the image. I’m still learning HTML and CSS and only just found out about AUI.
How do I customize something like this - color, size etc.

Edit 1 - I tried including the code, but that didn’t work. How do I add it in it’s own little box? :thinking: