I created a modal box and vertically centred it using a technique Chris Coyer mentioned. The only problem I\'ve found with it so far is that sometimes the box is offset by half
As I encountered same problem with subpixels in Chrome and in version 64 it still can't handle subpixel transform values , I decided to write small js script, that fixes subpixel problem.
You can find it on github. It simply rounds transform value to full pixel.