.tooltip {
  position: relative;
  display: inline-block;
  border-bottom: 1px dotted;
}

.tooltip .tooltiptext {
	visibility: hidden;
	background-color: black;
	color: white;
	border-radius: 10px;
	line-width: 1.5ex;
	text-align: center;
	/* Position the tooltip */
	position: absolute;
	z-index: 1;
}

.tooltip:hover .tooltiptext {
	visibility: visible;
}