What does "It's so [something]" mean?

Native speaker’s answer
Rebecca
"It's so [adjective]" is an informal expression that means something is very/extremely [adjective]. It's a phrase that places emphasis on the quality being mentioned through the use of "so". In this case, emphasis is being placed on the "80s" vibe. Ex: Look at that puppy! It's so cute! Ex: It's raining so badly! This is so terrible.