you can either adjust it via and input in extra.css template
Code:
.PageNav a {
color: red;
}
or go through to the Admincp >> Appearance >> Style properties scroll down and venture in PageNav, Link Groups and Tabs >> PageNav Page Link and adjust the colours in that area.
Edit: oh wait, I think i misunderstood you. The above may not work, if someone doesn't get to your post before i can respond again I need to go check up on that looking at your screenshot.
Edit: Yup venturing in the above will work by adjust to your preference.