how to align to center in css code example

Example 1: css align center

//HTML
<div class="parent">
	<span>Hello World</span>
</div>

//CSS
.parent {
  display: flex;
  justify-content: center;
  align-items: center;
}

Example 2: css align center

/* This works wonderfully when you know the size of
the thing you are centering. If you don’t know, or are 
thinking it might change and want to be future proof,
try this: */

.centered {
   position: fixed;
   top: 50%;
   left: 50%;
   /* bring your own prefixes */
   transform: translate(-50%, -50%);
}

/* The translate value for transform is based off the size
of the element, so that will center nicely. */

Example 3: css center alignment

.center {
  text-align: center;
  border: 3px solid green;
}