//**
  Change the box model for Mozilla, Webkit, IE8 and the future
  @param !bs
    [ content-box | border-box ]
=box-sizing(!bs)
  /* Mozilla (FireFox, Camino)
  -moz-box-sizing= !bs
  /* Webkit (Safari, Chrome)
  -webkit-box-sizing= !bs
  /* IE (8)
  -ms-box-sizing= !bs
  /* CSS3
  box-sizing= !bs