You can style the axes in Plot with AxesStyle. For example, the following code makes the axes red.
Plot[Sin[x], {x, -3, 3}, Axes -> True, AxesStyle -> Red] I cannot seem to find a way to style the polar axes in PolarPlot. AxesStyle does not work and there is no PolarAxesStyle function. I was hoping to get this code below to work but it doesn't.
PolarPlot[θ , {θ , 0, 3 Piπ}, PolarAxes -> True, AxesStyle -> Red] Is this a missing feature in Mathematica?