.sweet-alert .icon.custom{
  animation:vibrate 4s linear 0s infinite;
  -moz-animation: vibrate 4s linear 0s infinite;
  -webkit-animation: vibrate 4s linear 0s infinite;
  -o-animation: vibrate 4s linear 0s infinite;
}

@keyframes vibrate{
  0%   {margin-left: 45%;}
  25%  {margin-left: 40%;}
  50%  {margin-left: 45%;}
  75%  {margin-left: 40%;transform: rotate(-8deg);}
  100% {margin-left: 45%;}
}

@-moz-keyframes vibrate{
  0%   {margin-left: 45%;}
  25%  {margin-left: 40%;}
  50%  {margin-left: 45%;}
  75%  {margin-left: 40%;-moz-transform: rotate(-8deg);}
  100% {margin-left: 45%;}
}

@-webkit-keyframes vibrate{
  0%   {margin-left: 45%;}
  25%  {margin-left: 40%;}
  50%  {margin-left: 45%;-webkit-transform: rotate(-8deg);}
  75%  {margin-left: 40%;}
  100% {margin-left: 45%;}
}

@-o-keyframes vibrate{
  0%   {margin-left: 45%;}
  25%  {margin-left: 40%;}
  50%  {margin-left: 45%;}
  75%  {margin-left: 40%;-o-transform: rotate(-8deg);}
  100% {margin-left: 45%;}
}