Green balls on css

Styling the Balls on JS makes the balls appear blue until JS script is loaded, which makes them for a split second to flicker.

I added a balls.css (credits to @Dakota628 https://github.com/Dakota628/jenkins-clean-theme) that makes the balls not flicker. The JS is still applied on top of it (making the 3d effect), but now the blue color never appears on screen and it's much smoother.