Custom Dropdown Menu in Navbar not following given width

Hi there!

I have a problem with a custom dropdown menu in my navbar. I currently have two dropdown links in my navbar. I would like both to come down and cover half of the page. I have made this work with the first one (Collections), by simply setting a 50vw on the dropdown wrapper. However I am having issues with the second one (Contact), this appears to be right in the Designer, but it’s all over the place in the live site.

Any clues on what might fix this?

Read only site.