OK is unavailable when trying to change text color. Can you help?

I need your help. I'm trying to change the color of text located in the footer of my web site. Unfortunately, every time I open the text edit box and select a color, the OK button is unavailable. It appears to be below my laptop's task manager bar. (see att'd) I've tried to use the scroll bar to reveal the OK button, but as soon as I do, the text edit box closes.

I've granted access to my site for you. At a minimum, I'd like to change the phrase "Call Today!" to red.

Thank you in advance for your help!