Hello,
That header background image is controlled here:
Template.CSS - Line 516
#s5_header_area1 {
background: url("../images/s5_menu_bg.png") repeat scroll 0 0 rgba(0, 0, 0, 0);
display: block;
height: 114px;
overflow: hidden;
width: 100%;
z-index: 3;
}
Regards,