any ways to set the message colour ？

[JoneRen]

Is there any ways to set the message colour, when I use the dark mode, the message is also the black colour on ios 9, and it's able to change the button colours but no ways to set the message colour ? and also try every style all the message color is black in alter view.
970035af-7b95-4be4-adc2-78ec03f6b857

my codes:
[UIAlertController mz_applyCustomStyleForAlertControllerClass:[UIAlertController class]];
MZAlertControllerStyle *defaultStyle = [UIAlertController mz_sharedStyle];
defaultStyle.blurEffectStyle = UIBlurEffectStyleDark;
defaultStyle.backgroundColor = RF_WHITE_COLOR;
defaultStyle.defaultButtonColor = RF_WHITE_COLOR;
defaultStyle.destructiveButtonColor = RF_WHITE_COLOR;