#TheDress -- Blue/Black, White/Gold ... Sales are Through the Roof!!!

The company behind #TheDress has put the debate to bed -- it's blue and black -- and the hubbub has done wonders for its business ... thanks to the hashtag hysteria.

#TheDress phenomenon began after a woman posted a photo of her mother's dress for her wedding ... asking people to ID the color. From there ... EXPLOSION ... with the likes of Justin Bieber (blue and black), Kim Kardashian (white and gold), and Taylor Swift (blue and black) all weighing in.

A rep for the company that makes the dress, Roman Originals, tells TMZ the dress is blue and black, but it also comes in pink and black, white and black and red and black. There isn't a white and gold option yet ... but Roman is looking to add it to the line because of all the commotion.

As for business, Roman Originals says sales are up 347%.

And here you thought a few escaped llamas would be the weirdest thing to happen on the Internet this week.