Add a full-width image to the stacked header layout (Presidio)

If you have an image or logo file you’d like to feature as the full-width background of your stacked Presidio blog header, use the Code Hack below. Please note this Code Hack was written specifically for customers who only have their logo artwork as a single JPG file, with both blog name and background compressed together as one image. If you happen to have the background image for your header separate from the logo itself (with the logo available as PNG with a transparent background), use this Code Hack instead.