This is not a yukata. It is a kimono. The color is aquatint (pale mint ice). Due to storage or perhaps the original condition, there are distinct areas that are faintly grayed and areas that are not. It is unknown whether this can be improved by cleaning. The pattern appears to be waves, like the surface of water. I don't know anything about kimonos, so I will investigate within my knowledge. If you have any questions, please ask in the comments before purchasing. Please purchase only if you understand the condition.