.tooltip { 
  position: relative; 
  cursor: help; 
}

.tooltip::after {
  content: attr(data-tip);
  white-space: nowrap;
  position: absolute; 
  left: 50%; 
  top: 100%;
  transform: translateX(-50%) translateY(0.4rem);
  background: #334155; 
  color: #f8fafc;
  padding: 0.25rem 0.5rem; 
  border-radius: 0.25rem;
  opacity: 0; 
  pointer-events: none;
  font-size: 0.75rem; 
  line-height: 1;
  transition: opacity 0.15s ease;
  z-index: 10;
}

.tooltip:hover::after { 
  opacity: 1; 
}