.loader {
  position: absolute;
  visibility: hidden;
  left: 50%;
  top: 65%;
  z-index: 1;
  width: 120px;
  height: 120px;
  margin: -76px 0 0 -76px;
  border: 16px solid #f3f3f3;
  border-radius: 50%;
  border-top: 16px solid #3498db;
  -webkit-animation: spin 1s linear infinite;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

/* Tooltip container */
.mytooltip {
  position: relative;
  display: inline-block;
  border-bottom: 1px dotted black; /* If you want dots under the hoverable text */
}

/* Tooltip text */
.mytooltiptext {
  visibility: hidden;
  width: 150px;
  bottom: 100%;
  left: 50%;
  margin-left: -75px; /* Use half of the width to center the tooltip */
  background-color: rgba(0, 0, 0, 0.66);
  color: #fff;
  text-align: center;
  padding: 5px 0;
  border-radius: 6px;

  /* Position the tooltip text - see examples below! */
  position: absolute;
  z-index: 1;
}

/* Show the tooltip text when you mouse over the tooltip container */
.mytooltip:hover .mytooltiptext {
  visibility: visible;
}