[data-tooltip] {
  position: relative;
  display: inline-block;
}
[data-tooltip]::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 130%;
  left: 50%;
  transform: translateX(-50%);
  background: #777;
  color: #fff;
  padding: 4px 8px;
  border-radius: 4px;
  font-size: 11px;
  font-family: Arial, sans-serif;
  white-space: nowrap;
  visibility: hidden;
  opacity: 0;
  transition: 0.3s;
  z-index: 9999;
}
[data-tooltip]::before {
  content: "";
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 5px solid transparent;
  border-top-color: #777;
  visibility: hidden;
  opacity: 0;
  z-index: 9999;
}
[data-tooltip].tip-bottom::after {
  bottom: auto;
  top: 130%;
}
[data-tooltip].tip-bottom::before {
  bottom: auto;
  top: 100%;
  border-top-color: transparent;
  border-bottom-color: #777;
}
[data-tooltip]:hover::after, [data-tooltip]:hover::before {
  visibility: visible;
  opacity: 1;
}
/* Ajustement spécial pour la grande image Omega */
.tip-omega::after {
  top: 115% !important; /* On le remonte plus près de l'image */
}
.tip-omega::before {
  top: 92% !important; /* On remonte la flèche aussi */
}