This is the 1485th most frequent Russian word.
настроение
Mood.
Here, 'настроение' refers to the emotional state or mood of the subject.
У меня сегодня отличное настроение.
I am in a great mood today.
In this sentence, 'настроение' describes the general emotional tone or atmosphere of the setting.
Настроение в комнате стало напряжённым.
The mood in the room became tense.
Here, 'настроение' relates to the emotional effect produced by an external factor, music, in this case.