I want to change the background color of the Select File (nonlegacy) or Choose File (legacy) version of the File Upload Widget. Interestingly, on the web portal if i use the non legacy version and change the background-color of .button.primary.compact I can change the color, as well as the color of the Next button and all of the other functional buttons. But I want to only change the background color of the File Upload button. I am using version 4.5.1