JS changing gui box color

Hello, I need help getting the gui box that I have to turn yellow when my number var = 1. I have found some ways to do this but they are in C# and need one in JS. It is easy to get a button yellow but not a box for some reason. So if you could leave an example down below on how to get a GUI box yellow that would be great.

Thanks:)

There is very little difference when it comes to c# and unityscript. And, you can always checkout unity’s online docs for API help.

GUI.Color