Rhino Glass Color Issue

i'm working on a rhino file rn but when i change the material of my building to glass and chose specific colors for the different layers of glass, the rendered view shows that the buildings are all grey in color...i asked gemini and it keeps telling me its opacity issue n that i should change the properties of the glass but the properties window doesn't seem to allow me to change the opacity of my glass...does anyone know what i can do? my submission is tmr im crying thank you!