.sqs-gallery-design-grid-slide:hover {
    background-image: url(Orion.jpg);
    background-size: 100% 100% !important; }

.sqs-block-content .image-slide-anchor:hover img {
    display: none; }

   .sqs-gallery-design-grid-slide:hover {
    -webkit-transition: all 300ms cubic-bezier(0.420, 0.000, 0.580, 1.000); 
   -moz-transition: all 300ms cubic-bezier(0.420, 0.000, 0.580, 1.000); 
    -ms-transition: all 300ms cubic-bezier(0.420, 0.000, 0.580, 1.000); 
     -o-transition: all 300ms cubic-bezier(0.420, 0.000, 0.580, 1.000); 
        transition: all 300ms cubic-bezier(0.420, 0.000, 0.580, 1.000);  
         opacity: 0;

         }

a .image-block-wrapper:hover {
  -webkit-transition: all 300ms cubic-bezier(0.42, 0, 0.58, 1);
  -moz-transition: all 300ms cubic-bezier(0.42, 0, 0.58, 1);
  -ms-transition: all 300ms cubic-bezier(0.42, 0, 0.58, 1);
  -o-transition: all 300ms cubic-bezier(0.42, 0, 0.58, 1);
  transition: all 300ms cubic-bezier(0.42, 0, 0.58, 1);
  opacity: 0.7;
}

Hello, World! Working?