This is the 9615th most frequent Russian word.
хорошее
"Хорошее" means "good" (neuter form).
Here, 'хорошее' is used as an adjective modifying the noun 'настроение' (mood), describing it as good.
У тебя хорошее настроение.
You are in a good mood.
In this sentence, 'хорошее' describes 'решение' (decision), showing evaluation or quality of the noun.
Это хорошее решение.
This is a good decision.
Here, 'хорошее' functions substantively, referring to 'good things' or 'something good,' standing alone as the object in the sentence.