Ye & BC hit up The Grove for a movie date in Los Angeles Sunday ... apparently, checking out "Dune: Part 2" -- and Bianca's style was far more in line with what we've seen in the past.

Check out the pics ... Bianca went with the strapless, backless baby blue top and sheer white leggings during the flirty outing with her man -- who kept it simple in his usual all-black ensemble.

BTW ... Censori's got her stilettos on too -- an interesting choice for a matinee showing, but a classy look no doubt.

This back-to-basics style comes just hours after Ye and Bianca were spotted with West's eldest daughter North ... and Bianca rocked a giant fur coat.

The scene was pretty odd to see ... 'cause we're definitely not used to Bianca wearing much at all -- just take her other outfit at The Grove this past week as an example. Barely any clothing to be spoken of.

It seems she indeed covered up for 10-year-old North's benefit ... or, maybe she was just a little chilly Saturday. Either way, Censori's lookin' for more like herself during the afternoon outing.

In any case, it's probably good movie theaters are dark ... 'cause Bianca's outfit probably would've taken all eyes off the screen!!!