gistfile1.css

    img
      width: 116px
      -webkit-animation: swing 3s infinite ease-in-out
      -webkit-transform-origin: top
      -moz-animation: swing 3s infinite ease-in-out
      -moz-transform-origin: top
      float: left
      margin: -40px 0px 0 -130px
    .topic-dev
      img
        -webkit-animation-delay: .3s
        -moz-animation-delay: .3s
    .topic-ios
      img
        -webkit-animation-delay: .6s
        -moz-animation-delay: .6s

@-webkit-keyframes swing
  0%
    -webkit-transform: rotate(-3deg)
  50%
    -webkit-transform: rotate(3deg)
  100%
    -webkit-transform: rotate(-3deg)