Dropdwon menu issue

Site URL: https://garlic-paddlefish-yd4j.squarespace.com/

I have an issue with the drop down menu being blacked out... How do I make it translucent to the background gradient??

SIte password is Miranda

Also does anybody know how to make the gradient background I have coded in, go across seamlessly to new sections instead of this?

I'm no guru at CSS but I'd try this (from an earlier forum post):

.header-nav-folder-content {
  background: transparent !important;
}

Complete post here if you'd like to read: