.mediawrapper_block {
  float: left;
}

.mediawrapper_block a {
  display: table-cell;
  position: relative;
  text-align: center;
  vertical-align: middle;
}

.mediawrapper_block img {
  display: block;
  margin: auto;
}
.mediawrapper_block a { 
width: 418px;
height: 312px;
}