Make Centered Menu Logo in Transparency Disappear until Scroll

Thank you for your time.

I copied your CSS for centering a logo in a split menu from your page: http://graphitivity.com/enfold/docs/menu/#logo-center-split-menu. That part is working just fine.

I have the header set to transparency until scroll down. That part works fine too.

What I would like to do is make the menu items appear with no gap when the logo is invisible. Using the CSS as is at the moment, the logo disappears when I use a small 1px transparent png file for the transparent logo, but it remains at 150px on the margin right. How can I make it appear like this:

Item | Item | Item | Item | Item | Item

Until I scroll down, so that it looks like this:

Item | Item | Item | Logo | Item | Item | Item

Because right now in the header it looks like this:

Item | Item | Item | | Item | Item | Item

Hope that makes sense. Thank you in advance.