[rahimnathwani]

Focus on what you're expected to deliver (e.g. some working software) and how you're expected to deliver it (e.g. being nice to colleagues, writing design docs, ...).

If you don't know what's expected of you, that's something you could discuss with your manager.

If you're doing what is expected of you (and being nice to colleagues etc.) or, ideally, exceeding those expectations, then you will probably enjoy your job more, and feel less pressure to conform to specific work hours.

Of course, different companies and teams/managers have different cultures. Also, in some countries you're expected to stay later than your manager. She, in turn, is expected to stay later than her manager.