.popup-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.9);
  display: flex;
  align-items: center;
  justify-content: center;
  visibility: hidden; /* Start hidden */
  opacity: 0;        /* Start invisible */
  transition: visibility 0s, opacity 0.3s ease;
  z-index: 9999;     /* Highest z-index */
  overflow: hidden;
}

.popup-overlay.active {
  visibility: visible; /* Show when active */
  opacity: 1;         /* Make visible */
}

.popup-content {
  background-color: #fff;
  padding: 30px;
  border-radius: 10px;
  text-align: center;
  max-width: 500px;
  width: 90%;
  box-shadow: 0 0 15px rgba(0, 0, 0, 0.5);
  font-size: 1.2em;
  font-weight: bold;
}