#imggallery {
  position: relative;
}

#imggallery img {
  -webkit-transition: .5s ease;
  transition: .5s ease;
}

#imggalley button {
position: absolute;
top: -5px;
right: 10px;
opacity: 0;
-webkit-transition: .5s ease;
transition: .5s ease;
}

#imggallery:hover img, 
#imggallery:focus img {
    opacity:0.8;
}


#imggallery:hover button, 
#imggalley:focus button {
  opacity: 0.8;
}