Before reading the main content I just wanted to address this: This should be a feature that's already easily integrateable as I think this is a pretty basic yet critical option to have in any theme. With all the varying screen sizes, why limit yourself?

I have an issue with large screens.

If I get a screen over like 1400x900 or so, Andromeda's header background (that black rectangle that's about 1500x490 behind the slideshow and header) stops repeating (or just simply stops, not repeating at all) and you have two ugly white spaces outside of the header background.

I'm trying to get the background to be dynamic just like I got my content to be dynamic. (Dynamic meaning the content expands and contracts as I expand and contract my window size.) So whether you have an 1024x768 or 2500x3100, I want the header background to be filling the width of the screen.

I was trying to customize the layout.css, but I don't know how to do it. I will tell you that in the "page wrap" section of the layout.css, I added width:100%; and it caused the content to be dynamic, but this method didn't seem to work on the header, or maybe I put the code in the wrong place.

I've tried and tried again, no hope for me. Please help!

FIXED!

For anyone happening to stumble upon this same issue, here is this fix

body.with-slideshow {
  background:url('../images/bg-pattern-t.gif') repeat-x center top #F5F5F5;
<strong> clear:both;</strong>
}

The clear:both; alias is what saved me, it has to do with disallowing any floating elements to either side of the image. Not exactly sure how it worked but it did!