Changing the background colour for the pop up box in UWL

Hello Expert,

I got the confirmation popup box In my UWL application for the confirmation process. By default the background for this popup box is Blue.

I want change it to new colour.

FYI, I have an Iview from web dynpro Application for this popup. How can I change this?

Kindly advice.

Regards,

Hafizah.