The introductory text has a couple of settings users can control:
Background Color:
Cream (default) According to the VA GUI conventions, this is the background color that should be used with text that users cannot edit.
White For clarity and brightness.
Font:
When users press the "Change Font" button they are presented with a Font form that can be used to change the font face, style, size, and color of the introductory text of the signon window.