How to remove gap between header and edge border?

I have what appears to be a 1-pixel gap at the top of the header, which allows the background image to bleed through. It's not a major issue but is distracting. Above the main header there is the pixel gap and then about a 1/8th-inch white edge border above that (see picture). How do I remove the gap (shift the small edge border down a pixel)? Thanks!

 

Hello,

Paste this code in Custom CSS
Appearance > Theme Option > Styling Option > Custom CSS

Code:

.header {
padding-top: 0px;
}

 

Thanks for the response back. It's weird - just realized that it's only doing this on my work laptop on Chrome. Looks fine in IE, or on either browser on other machines. Don't know why, but it's clearly not a code issue so I won't worry about it. Thanks again!