There's also lot simpler explanation if moon is near horizon. (scattering of light in atmosphere)
You could tell more details. (like time)
Did it look like that?
It's taken after Pinatubo's eruption but there haven't been any biger eruptions now.
Noctilucent clouds are other possibility but normally they don't have much colors.
One other possibility is pearl cloud.
Also rocket launchs can leave very colorful "clouds".