I found the issue, I have a fresh quickstart installation of JaMorgan demo site on my local server.
The issue is with theme style-3 on the pages with Masthead module. The collapsed menu for small screen, some links are not clickable. The issues disappears if you disable the masthead for that specific page.
On the demo site, style-3 doesn't have a page with masthead, so apply style-3 to any page with a masthead and have a look to the collapsed menu. Some linked cannot be clicked, they don't link anywhere.
For instance, apply theme style--3 to the News & Update page; on small screens, try the collapsed menu (not the sidebar one): About Us and Services can't be clicked.
Can we fix that?
Thanks.