.overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.4); /* Light black overlay */
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  text-align: center;
}
img.img-fluid.auto_size {
    height: 465px;
}
img.img-fluid.ser-img {
    height: 256px;
}