Yes, you're right.
I've reported the following alternative answers as well: .

Seragam kami berwarna biru. = not accepted, reported
Seragam kami biru. = not accepted, reported
Seragam kita warnanya biru. = not accepted, reported
Seragam kita berwarna biru. = not accepted, reported
Seragam kita biru. = not accepted, reported