Why is the back cover of the Xiaomi Pad 7/Xiaomi Pad 7 Pro so light in color and looks like gray?

To present a refreshing and understated aesthetic, the color of the Xiaomi Pad 7/Xiaomi Pad 7 Pro is natural light green. And the back cover is made of metal material, which will be affected by ambient light and show a certain degree of color cast, so sometimes you may feel it is gray. It is normal and will not affect normal use.