.op-slider {
  width: 100%;
  position: relative;
  overflow: hidden;
}

.op-slides {
  position: relative;
  width: 100%;
}

.op-slide {
  position: absolute;
  width: 100%;
  opacity: 0;
  transition: opacity 0.6s ease;
}

.op-slide.active {
  opacity: 1;
  position: relative;
}

.op-slide img {
  width: 100%;
  height: auto; /* 👈 auto height */
  display: block;
}

/* Navigation buttons */
.op-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(0,0,0,0.5);
  color: #fff;
  border: none;
  padding: 12px 16px;
  cursor: pointer;
  font-size: 18px;
  z-index: 10;
}

.op-prev { left: 10px; }
.op-next { right: 10px; }

.op-nav:hover {
  background: rgba(0,0,0,0.7);
}

/* Mobile friendly */
@media (max-width: 768px) {
  .op-nav {
    padding: 8px 12px;
    font-size: 16px;
  }
}