body {
  background-color:#D83530;
  color: black;
  font-family: Georgia, serif
.hover_image:hover {text-decoration: none} /* Optional (avoid undesired underscore if a is used as wrapper) */
.hide {display:none}
/* Do the shift: */
.hover_image:hover img:first-child{display:none}
.hover_image:hover img:last-child{display:inline-block}