Hello to both of you.
The resolution to this problem is simple. As far as I understand heatheraglow is asking how to remove or increase transparency of dark overlay over the header of the site.
If that is correct, then do:
1. Open Editor @ style.css
2. Go to .site-header section (press F to find it)
3. You will find a code:
.site-header::after {
content: ”;
width: 100%;
height: 100%;
position: absolute;
top: 0;
left: 0;
background-color: rgba(0, 0, 0, 0.15);
4. In the background section, last number is responsible for transparency. 0 is full transparency 1 is null transparency