That’s weird, the menu’s <ul> tag and <li> tags does not have classes? Do you have a custom navbar template? If not, please update your X|Theme to latest version (4.6.4) and Cornerstone to (1.3.3) since you already have updated your WordPress to version (4.7).
Currently you have X|Theme v4.3.0 and Cornerstone v1.3.0.