css a img center code example

Example 1: html center image

/* It's better practice to do this in CSS, not HTML. 
So here is the CSS code! */
img {
  display: block;
  margin-left: auto;
  margin-right: auto;
}

Example 2: center an image

.someclass {
  display: block;
  margin-left: auto;
  margin-right: auto;
}