place an image in the middle of a div code example

Example 1: how to center an image element inside a block in css

img { display:block;
      margin-left: auto;
      margin-right:auto;
      }

Example 2: position images in center of container

.image-container {
    width: 500px;
    height: 500px;
    position: relative;
}

.image-container img {
    position: absolute;
    right: 0;
    left: 0;
    top: 0;
    bottom: 0;
    margin: auto auto;
}