align image in center in 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: css center

// example 1 
div { display: grid; place-items: center; }

// example 3
div{ display:flex; align-items:center; }

// example 3
div { width: 100%; margin: 0 auto; }