Banner Picture Location

Where do I go to change the banner background image? It is larger on the home page and I want to change both.

I'm able to change the logo and the menu already, but not the background - see attached.

for inner pages, template_css.css:

.sparky_inner .toprow {
background: url(../images/custom/topmenu_bg1.jpg) no-repeat;
background-size: cover;
}

for home page it is carousel.

Thanks, Ivan. Worked perfectly.