[Mobile] Slightly different appearance at 767px and 768px width

[nscyclone]

768px used to be a common width breakpoint. But there is a place where 767px is used instead.
This causes a slightly different appearance at 767px and 768px: 768px screen width seems to be considered as a mobile device but .visible-xs blocks designed for it won't appear.

767px:

768px:

769px: