I'm trying to change the color of the welcome text, and I have found the place( Configure-design) to change the actual text, but no way to change the color. Any ideas about where to look?
Changing color of welcome text from backend is not possible, you need to define in theme css file.
If you are using custom theme, some custom theme provide option to write custom css in backend also. you can use that option also to write css in custom theme.