@keyframes float {
  50% {
    transform: translateY(-3.5%);
    -webkit-transform: translateY(-3.5%);
    -moz-transform: translateY(-3.5%);
    -ms-transform: translateY(-3.5%);
    -o-transform: translateY(-3.5%);
}
  0%, 100% {
    transform: translateY(0);
    -webkit-transform: translateY(0);
    -moz-transform: translateY(0);
    -ms-transform: translateY(0);
    -o-transform: translateY(0);
  }
}

.animate-float{
    animation: float 2500ms ease-in-out ;
    -webkit-animation: float 2500ms ease-in-out ;
    animation-iteration-count: infinite;
}