.galleria {
  position: relative;
  overflow: hidden;
}

.galleria > div {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  opacity: 0;
  transition: opacity 0.6s ease;
}

.galleria > div.active {
  opacity: 1;
  position: relative;
}

.galleria-btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  background: rgba(0, 0, 0, 0.45);
  color: #fff;
  border: none;
  padding: 0;
  width: 44px;
  height: 44px;
  font-size: 2rem;
  line-height: 44px;
  text-align: center;
  border-radius: 50%;
  cursor: pointer;
  transition: background 0.2s;
  user-select: none;
}

.galleria-btn:hover {
  background: rgba(0, 0, 0, 0.75);
}

.galleria-prev {
  left: 12px;
}

.galleria-next {
  right: 12px;
}