Cognizant interview questions

Recruiter did a phone screen, followed by a peer level Sr Director interview. Thereafter there was a panel interview for a case study. The panel members were constantly looking at me like a hawk during the case study prep time. Then the last round was the hiring manager. This was a big red flag. Hiring manager pokes holes in resume and clearly gives body language that he is not interested in proceeding. I felt this was a very disrespectful and unprofessional attitude by a hiring manager.

first gaming and coding are easy but it is somewhat tasky for communication round and the interview was a basic questions they have asked me prime number code and some of the questions on html ,css and javascript