Comments box backdrop div missing

Added
LB-656:Locally deployed Embed URL (stt theme) -> YouTube video was halved when the iPad was hold in vertically long position

Resolved for frontend themes.
Styling embed user comment posts

Finished
Conflicts resolved
Merge pull request #181 from nidzix/user-comments-fix

LB-656:Locally deployed Embed URL (stt theme) -> YouTube video was ha…