how to fix spacing issue on navigation

I have been able to successfully add a link to a folder by following this post

but now there is extra space in my navigation. There is some suggestions to add custom css to fix spacing issues in the navigation. However this is not working for me and I was hoping you would be able to assist. 

https://forum.squarespace.com/topic/11723-how-do-i-link-a-folder-title-within-the-navigation-to-a-page/page/2/

I still have extra spacing in my navigation and on mobile it looks the same as well.

You can see it on PalazzodelGolfo.com

 //remove extra spacing from added link to folder 
#navigation-folder-hack { margin-left: -30px; } @media only screen and (max-width: 640px) { //fix navigation-folder-hack for mobile 
#navigation-folder-hack { margin-left: 0px; display:inline !important; } }

I think that a better mobile experience would be a navigation that was completely flat however and I'd like to hide the "+" sign. Can I do that?

@sullisnyc Can you take screenshot of spacing & "+" sign?