assets/css/tooltip.css

[tooltip] {
  position: relative;
  display: inline-block;
}

[tooltip]::before {
  transition: 0.3s;
  content: '';
  position: absolute;
  top: -6px;
  left: 50%;
  transform: translateX(-50%);
  border-width: 4px 6px 0;
  border-style: solid;
  border-color: rgba(25 30 56) transparent transparent;
  z-index: 99;
  opacity: 0;
}

[tooltip]::after {
  transition: 0.3s;
  white-space: nowrap;
  content: attr(tooltip);
  position: absolute;
  left: 50%;
  top: -6px;
  transform: translateX(-50%) translateY(-100%);
  background: rgba(25 30 56);
  text-align: center;
  color: #fff;
  font-size: 0.875rem;
  min-width: 80px;
  max-width: 420px;
  border-radius: 3px;
  pointer-events: none;
  padding: 4px 8px;
  z-index: 99;
  opacity: 0;
}

[tooltip]:hover::after,
[tooltip]:hover::before {
  opacity: 1;
}