I've just changed my journal layout to Modular by branchandroot and I'm having issues putting a header banner in. I want it to show above the header box with the journal title, 'Latest entries' etc in - at the top of the page below the nav bar - but the CSS code that I know puts it in the header, in that box.

The CSS in question is

#header {
margin-top: 5px;
background-image: url('https://sharpiefan.dreamwidth.org/file/5524.png');
background-repeat: no-repeat;
background-position: top center;
padding-top: 275px;
}


What should I change in order to position the header above that top box? (It doesn't look as if posting the image URL into the provided area in the Images area of 'Customise your theme' does anything at all, so that's not much help either.)

It's been a long time since I changed my journal layout, I'm willing to accept I might be missing something really obvious!