На что ругается валидатор?

Question

[Александр Коновалов]

Здравствуйте! Есть такая анимация:

@-webkit-keyframes flip {
  from {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, -360deg);
    transform: perspective(400px) rotate3d(0, 1, 0, -360deg);
    -webkit-animation-timing-function: ease-out;
    animation-timing-function: ease-out;
  }

  40% {
    -webkit-transform: perspective(400px) translate3d(0, 0, 150px) rotate3d(0, 1, 0, -190deg);
    transform: perspective(400px) translate3d(0, 0, 150px) rotate3d(0, 1, 0, -190deg);
    -webkit-animation-timing-function: ease-out;
    animation-timing-function: ease-out;
  }

  50% {
    -webkit-transform: perspective(400px) translate3d(0, 0, 150px) rotate3d(0, 1, 0, -170deg);
    transform: perspective(400px) translate3d(0, 0, 150px) rotate3d(0, 1, 0, -170deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }

  80% {
    -webkit-transform: perspective(400px) scale3d(.95, .95, .95);
    transform: perspective(400px) scale3d(.95, .95, .95);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }

  to {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }
}

@keyframes flip {
  from {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, -360deg);
    transform: perspective(400px) rotate3d(0, 1, 0, -360deg);
    -webkit-animation-timing-function: ease-out;
    animation-timing-function: ease-out;
  }

  40% {
    -webkit-transform: perspective(400px) translate3d(0, 0, 150px) rotate3d(0, 1, 0, -190deg);
    transform: perspective(400px) translate3d(0, 0, 150px) rotate3d(0, 1, 0, -190deg);
    -webkit-animation-timing-function: ease-out;
    animation-timing-function: ease-out;
  }

  50% {
    -webkit-transform: perspective(400px) translate3d(0, 0, 150px) rotate3d(0, 1, 0, -170deg);
    transform: perspective(400px) translate3d(0, 0, 150px) rotate3d(0, 1, 0, -170deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }

  80% {
    -webkit-transform: perspective(400px) scale3d(.95, .95, .95);
    transform: perspective(400px) scale3d(.95, .95, .95);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }

  to {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }
}

.animated.flip {
  -webkit-backface-visibility: visible;
  backface-visibility: visible;
  -webkit-animation-name: flip;
  animation-name: flip;
}

@-webkit-keyframes flipInX {
  from {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, 90deg);
    transform: perspective(400px) rotate3d(1, 0, 0, 90deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
    opacity: 0;
  }

  40% {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, -20deg);
    transform: perspective(400px) rotate3d(1, 0, 0, -20deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }

  60% {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, 10deg);
    transform: perspective(400px) rotate3d(1, 0, 0, 10deg);
    opacity: 1;
  }

  80% {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, -5deg);
    transform: perspective(400px) rotate3d(1, 0, 0, -5deg);
  }

  to {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
  }
}

@keyframes flipInX {
  from {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, 90deg);
    transform: perspective(400px) rotate3d(1, 0, 0, 90deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
    opacity: 0;
  }

  40% {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, -20deg);
    transform: perspective(400px) rotate3d(1, 0, 0, -20deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }

  60% {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, 10deg);
    transform: perspective(400px) rotate3d(1, 0, 0, 10deg);
    opacity: 1;
  }

  80% {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, -5deg);
    transform: perspective(400px) rotate3d(1, 0, 0, -5deg);
  }

  to {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
  }
}

.flipInX {
  -webkit-backface-visibility: visible !important;
  backface-visibility: visible !important;
  -webkit-animation-name: flipInX;
  animation-name: flipInX;
}

@-webkit-keyframes flipInY {
  from {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, 90deg);
    transform: perspective(400px) rotate3d(0, 1, 0, 90deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
    opacity: 0;
  }

  40% {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, -20deg);
    transform: perspective(400px) rotate3d(0, 1, 0, -20deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }

  60% {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, 10deg);
    transform: perspective(400px) rotate3d(0, 1, 0, 10deg);
    opacity: 1;
  }

  80% {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, -5deg);
    transform: perspective(400px) rotate3d(0, 1, 0, -5deg);
  }

  to {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
  }
}

@keyframes flipInY {
  from {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, 90deg);
    transform: perspective(400px) rotate3d(0, 1, 0, 90deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
    opacity: 0;
  }

  40% {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, -20deg);
    transform: perspective(400px) rotate3d(0, 1, 0, -20deg);
    -webkit-animation-timing-function: ease-in;
    animation-timing-function: ease-in;
  }

  60% {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, 10deg);
    transform: perspective(400px) rotate3d(0, 1, 0, 10deg);
    opacity: 1;
  }

  80% {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, -5deg);
    transform: perspective(400px) rotate3d(0, 1, 0, -5deg);
  }

  to {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
  }
}

.flipInY {
  -webkit-backface-visibility: visible !important;
  backface-visibility: visible !important;
  -webkit-animation-name: flipInY;
  animation-name: flipInY;
}

@-webkit-keyframes flipOutX {
  from {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
  }

  30% {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, -20deg);
    transform: perspective(400px) rotate3d(1, 0, 0, -20deg);
    opacity: 1;
  }

  to {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, 90deg);
    transform: perspective(400px) rotate3d(1, 0, 0, 90deg);
    opacity: 0;
  }
}

@keyframes flipOutX {
  from {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
  }

  30% {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, -20deg);
    transform: perspective(400px) rotate3d(1, 0, 0, -20deg);
    opacity: 1;
  }

  to {
    -webkit-transform: perspective(400px) rotate3d(1, 0, 0, 90deg);
    transform: perspective(400px) rotate3d(1, 0, 0, 90deg);
    opacity: 0;
  }
}

.flipOutX {
  -webkit-animation-name: flipOutX;
  animation-name: flipOutX;
  -webkit-backface-visibility: visible !important;
  backface-visibility: visible !important;
}

@-webkit-keyframes flipOutY {
  from {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
  }

  30% {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, -15deg);
    transform: perspective(400px) rotate3d(0, 1, 0, -15deg);
    opacity: 1;
  }

  to {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, 90deg);
    transform: perspective(400px) rotate3d(0, 1, 0, 90deg);
    opacity: 0;
  }
}

@keyframes flipOutY {
  from {
    -webkit-transform: perspective(400px);
    transform: perspective(400px);
  }

  30% {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, -15deg);
    transform: perspective(400px) rotate3d(0, 1, 0, -15deg);
    opacity: 1;
  }

  to {
    -webkit-transform: perspective(400px) rotate3d(0, 1, 0, 90deg);
    transform: perspective(400px) rotate3d(0, 1, 0, 90deg);
    opacity: 0;
  }
}

.flipOutY {
  -webkit-backface-visibility: visible !important;
  backface-visibility: visible !important;
  -webkit-animation-name: flipOutY;
  animation-name: flipOutY;
}

Валидатор говорит "Извините, но правило @-webkit-keyframes не реализовано." В чем проблема, что ему не нравится?