.gallery-thumb{
  width: 100%;
  filter: grayscale(60%);
  transition: all 0.5s;
  border-radius: 3px;
}
.gallery-thumb:hover{
  filter: grayscale(0%);
  box-shadow: 0px 3px 6px rgba(0, 0, 0, .2);
  -webkit-transform: scale(1.05) rotate(0deg);
     -moz-transform: scale(1.05) rotate(0deg);
      -ms-transform: scale(1.05) rotate(0deg);
       -o-transform: scale(1.05) rotate(0deg);
          transform: scale(1.05) rotate(0deg);
  animation-fill-mode: forwards;
  -webkit-animation: gal-hov .45s;
     -moz-animation: gal-hov .45s;
      -ms-animation: gal-hov .45s;
       -o-animation: gal-hov .45s;
          animation: gal-hov .45s;
}

@-webkit-keyframes gal-hov {
  75%{
    -webkit-transform: scale(1.2) rotate(-2deg);
     -moz-transform: scale(1.2) rotate(-2deg);
      -ms-transform: scale(1.2) rotate(-2deg);
       -o-transform: scale(1.2) rotate(-2deg);
          transform: scale(1.2) rotate(-2deg);
  }
  100%{
    -webkit-transform: scale(1.05) rotate(0deg);
     -moz-transform: scale(1.05) rotate(0deg);
      -ms-transform: scale(1.05) rotate(0deg);
       -o-transform: scale(1.05) rotate(0deg);
          transform: scale(1.05) rotate(0deg);
  }
}

@media only screen and (min-width: 991px) {
  .gallery-thumb{
    height: 150px;
  }
}

@media only screen and (max-width: 991px) {
  .gallery-thumb{
    height: 220px;
  }
}