align an image inside a div code example

Example 1: centre align image in div

body {
  margin: 0;
}

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

Example 2: how to center an image element inside a block in css

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