Can We Make the Header Transparent and Add a Full-Window Image That Will Show through the Header and Fill the Window Edge-to-Edge?

Making the Header Transparent

You currently can’t control the opacity of your color through the theme options panel. But you can always set the opacity of a color through your custom CSS box.

Setting the Header to Span From Edge to Edge

You can set the max width to be a very large number. This way your header and footer will always span from edge to edge.