Mood: The mood of the video appears to be nostalgic and possibly melancholic, with a hint of playfulness. The theme seems to revolve around heartbreak or longing, as suggested by the title 'Phir Kya Hai Gham', which translates to 'What is the sorrow then?'. The overall emotion conveyed is one of introspection and contemplation.

Environment: The setting of the video seems to be a classroom or educational environment, as indicated by the chalkboard background on the left side and the equations visible on the wall behind the woman on the right side. The warm, golden lighting and the presence of mathematical equations suggest a sense of nostalgia and reminiscence.