.center-images {
    display: flex;
    flex-direction: column;
    align-items: center;
}

/* Typically phone screens (taller than wide) */
@media (max-aspect-ratio: 3/4) {
  .center-images img {
    width: 100%;
  }
}

/* Typically computer or tablet screens (wider than tall) */
@media (min-aspect-ratio: 4/3) {
  .center-images img {
    width: 75%;
  }
}