animate-intro.css

-webkit-animation-name: intro-right;
-webkit-animation-duration: 0.5s;
-webkit-animation-iteration-count: once;
-webkit-animation-timing-function: ease-out;
-webkit-animation-delay: 0s;
-webkit-animation-fill-mode: both;

-webkit-animation-name: intro-left;
-webkit-animation-duration: 0.5s;
-webkit-animation-iteration-count: once;
-webkit-animation-timing-function: ease-out;
-webkit-animation-delay: 0.3s;
-webkit-animation-fill-mode: both;

@-webkit-keyframes intro-right {
  from {
    -webkit-transform: translateX(-100px);
    opacity: 0;
  }
  to {
    -webkit-transform: translateX(0px);
    opacity: 1;
  }
}

@-webkit-keyframes intro-left {
  from {
    -webkit-transform: translateX(100px);
    opacity: 0;
  }
  to {
    -webkit-transform: translateX(0px);
    opacity: 1;
  }
}