I am seeing the same issue as yanksno1 and Wolfe_CH. It seems to be affecting all forums and subforums when using the black theme. I am using Firefox as my browser. When looking at the source, the page number jump list is using a CSS class identified as 'pn-num HM-tool' whereas the previous and next numbers at the top of the page seem to be using the 'pn-num tooltip' class.
I hope this helps.
My screenshot is a cut-down example from the Audio > Subwoofer forum that highlights the issue and shows both page number styles.