UX of voting buttons

Please can you improve the contrast/affordance of the voting buttons on this forum?

At the moment all that happens when one is selected is there’s a slightly darker circle, and I often have to look really closely to work out if I’ve already up- or down-voted a post.

e.g. the difference between these two (current and proposed):

Thanks for the feedback, this does sounds like a good idea. I will mention it to my team.