how to centre vertically in css code example

Example 1: css align center vertical and horizontal

.parent-class {
  display: flex;
  align-items: center;
  justify-content: space-around;
}

Example 2: css center vertically

<style>
.container {
  height: 200px;
  position: relative;
  border: 3px solid green;
}

.center {
  margin: 0;
  position: absolute;
  top: 50%;
  left: 50%;
  -ms-transform: translate(-50%, -50%);
  transform: translate(-50%, -50%);
}
</style>

<div class="container">
  <div class="center">
    <p>I am vertically and horizontally centered.</p>
  </div>
</div>

Example 3: css center div

<!-- 
	 Simple CSS CENTER DIV Example
 	 
	 * See Fiddle in link for PoC *
-->

<div class="parent">
  <div class="child">
    <p>
      Eh Up Me Duck!
    </p>
  </div>
</div>

<style>
.parent {
  /* Just for aesthetics: see fiddle */
  border: 1px solid black;
  padding: 2px;
}

.child {
  border: 1px solid red;
  width: 50%;
  
  /* This is where the magic happens */
  margin-left: auto;
  margin-right: auto;
  /**********************************/
}

p {
  /* As you do */
  text-align: center;
}
</style>