When viewing the links from any parent menu item that has sub-menus will not work on iPhones.

Example: http://everroofsupport.com/new/
When viewed on a desktop computer the 'Systems & Specs' menu, which has a sub-menu works great. The main menu goes to the correct page and so does the sub-menu. When I view it on an iPhone 5, 6 or 7 we cannot click to the 'Systems & Specs' page at all. The menu opens up the sub-menu options only. Same applies to the 'Library' menu item and the 'Contact Us' menu tab. Is there a way to fix this?