It's the (apparent) shade of grey, Elizabeth. That slate (very blue grey) tone is one of my most flattering. I like the idea of being able to wear a fun but unflattering citron for a change due to that background. But I won't be buying -- not a need.
Vivian, I like that top, too, but agree it looks like summer. Then again, it's all relative. It's still in the 90s in Texas. Those ladies need something nice to wear in autumn, too.