.mega-cat-menu {
  list-style: none;
  margin: 0;
  padding: 0;
}
.mega-cat-menu li {
  padding: 12px 16px;
  background: #f5f5f5;
  margin-bottom: 2px;
  cursor: pointer;
  transition: all 0.3s ease;
}
.mega-cat-menu li:hover {
  background-color: #ddd;
}
.cat-panel {
  display: none;
  animation: fadeIn 0.3s ease-in-out;
}
.cat-panel.active {
  display: block;
}
.cat-panel img {
  max-width: 100%;
  height: auto;
  margin-bottom: 10px;
}
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}