Font color change in axis components

Good morning all. I hope you can help me with my problem. I want to change the font color of individual components in an axis. The horizontal axis at the bottom of one of my charts shows three groups of names. I'd like for each group to be a different color for easier viewing. Can this be done? I can change the chart column colors if necessary, but I'd still like to know if it's possible to mix the font colors in the axis.

Thanks.