.tooltip-container {
  position: relative;
  display: inline-block;
}

.tooltip {
  visibility: hidden;
  background-color: gray;
  color: #fff;
  text-align: center;
  padding: 2px;
  border-radius: 4px;
  position: absolute;
  z-index: 1;
  bottom: -15%;
  left: 50%;
  margin-left: 40px;
  opacity: 0;
  width: 100px;
  animation: fadeout 3s;
}

.hidden {
  visibility: hidden;
  position: absolute;
}

a {
  text-decoration-line: none;
}

a:hover {
  text-decoration-line: underline;
}

@keyframes fadeout{
  from{opacity: 1; visibility: visible}
  to{opacity: 0; visibility: hidden}
}