My daughter plays the same games (e.g. Minecraft) as the boys. She plays with the same Lego bricks as the boys. It's not that she doesn't see the differences, especially at school - it's that we don't make the differences seem like anything to worry about at this point.
By the time those differences matter more, I hope to have her self-confidence to the point where she'll kick those boys' butts.
While I don't argue that the majority of lego sets are geared towards boys they still run the Lego City line as well as the Harry Potter line which does seem to be relatively popular with girls. (My Ex-gf played with legos and loved the Harry Potter Stuff.)
Lego sets may be geared towards boys for the most part but plain lego bricks are about the most gender neutral toy you could possibly find. And it seems that kids of either gender (and any age!) appreciate them equally.
By the time those differences matter more, I hope to have her self-confidence to the point where she'll kick those boys' butts.