Header seems to be covering advertising leaderboard

I am transitioning a client's site from 7.0 to 7.1 and am almost finished. I put in their script (Code Injection for site) for their advertising that worked fine in 7.0 but in 7.1 it displays behind the semi-transparent header. 

Any clue as to why it is happening or how to remedy it?

Hi,

What is site url?

Still in the works but ss built-in domain is : cuboid-parrotfish-f32r.squarespace.com

I am wondering if I can target the element for the header background and reduce the top padding to allow the ad to show?

Thank you! That worked great!

One more item... it does not display properly in mobile. How would I change the mobile setting?

I think I figured it out...

display of header and ad//
@media only screen and (max-width: 640px) {header#header:not(.shrink) {
    margin-top: 50px;
}}