img {
  max-width: 500%;
  height: auto;
}

.zoom-container {
  width: 100%;             /* Fits the width of the iPhone screen */
  height: 300px;           /* Set the desired height of your viewport */
  overflow: hidden;        /* Crucial: Hides the parts of the image that spill out */
  position: relative;
}

.zoomed-image {
  width: 100%;
  height: 100%;
  transform: scale(1.5);   /* Zoom factor: 1.5 equals 150% zoom */
  transform-origin: center; /* Zooms into the center of the image */
}