Don't get naked
Ninja pants are a must.
Ask your recruiter if you don't know. Usually wearing a dress shirt is fine. No ties no suits needed. Suits will feel out of place fast. Only people I see in suit regularly are clients or special guests that have professional outfit as their dress code.
Bikini
Hoodies and flip flops
Business casual never fails. If you wear a suit, you probably wont get the job though
Dress doesn't matter, only code.
A grey tshirt is a must , rest optional
Business Casual
Only serious answer lol
Given how The Zuck dresses I was tempted to say Casual but bought it better to play safe as not everyone at FB is like that