Britney Spears To Bride -- You Worked It, Bitch ... Now Here's Your Wedding Gift

Britney Spears just surprised the newlywed bride who became a viral video star -- thanks to Brit's music -- with an awesome wedding gift ... backstage passes to meet Britney in Vegas.

Sources connected to Stephanie Huntington and her husband tell us Britney's people reached out to Stephanie after seeing the popular video from their wedding reception ... where Steph's Man of Honor leads a full-blown dance performance of "Work, Bitch."

We're told Britney's manager invited Stephanie and two friends to a surprise meet-and-greet last weekend ... where Brit took the optimistic step to invite herself to Stephanie's 10-year anniversary party.