Church colors?

-K- started preschool last week. She is having a blast. She really loves it. She loves to learn and have interaction with other kids. The first day of school, they were learning colors. She had little circles of all the colors and was telling me all the names. She held up the yellow and asked, "Mom, is this a church color?" I couldn't figure out what she was talking about. Then I realized.......A Primary color. I said "Yellow is a primary color.  She said "Yeah, a church color." (At our church, the classes the children attend are called Primary classes).