Does "Con mèo của bạn là màu trắng" also correctly translate as "Your cat is white"?
It is written in the annotations to the lesson. In Vietnamese people use "có" to say something is of a certain colour. Formula for this: S + có + màu + color. (Example: Con chó có màu nâu (literally, The dog has color brown)). Do not use “to be” with color. When translated to English, it means "The dog is brown".