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<p><a class="tooltip" href="#" target="_blank">Your text or image goes here
<span>Your custom pop up info here</span>

<!--[if IE]>
<span style="background-color: black;">Your custom pop up info here</span>
<![endif]-->
</a>
</p>
a.tooltip {
  position: relative;
  cursor: help;
}

a.tooltip span {
  display: none;
  position: absolute;
  top: 20px;
  left: 50px;
  width: 270px;
  padding: 5px;
}

a.tooltip: hover {
  display: inline;
}

a.tooltip:hover span {
  display: block;
  border: 2px solid #990000;
  color: white;
  font-size: 14px;
  background-color: rgba(36, 36, 36, 0.7);
}