Cardi B and Offset Party with TakeOff on His 25th Birthday

Takeoff was the man of the hour at his beverage-fueled surprise 25th birthday party ... but Cardi B made sure to grab some -- okay most -- of the attention.

Cardi and her husband, Offset, joined Quavo to celebrate the bday of their fellow Migos rapper in downtown L.A. Tuesday night, and the party theme was sweet ... as in loaded with sugary drinks, candy and cake.

The bash looked fun as hell too ... with a variety of arcade games, delicious food, and of course -- TakeOff's Drank Factory. According to Quavo, the party was thrown as a surprise for his pal ... he shared a post saying, "Surprise Take U Deserve It!!!"

Yes, sir!

As for the cake ... Cardi showed off plenty in a black fishnet getup accentuating her backside. Following her wardrobe malfunction at Bonnaroo, it appears she decided to go with a "less is more" approach to her outfit.