Check out example codes for "css align items vertical center". It will help you in understanding the concepts better.

Code Example 1

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style type="text/css">
      div {
        display: table-cell;
        width: 250px;
        height: 200px;
        vertical-align: middle;
      }
    </style>
  </head>
  <body>
    <div>Vertically aligned text</div>
  </body>
</html>

Code Example 2

div
{
	display: block;
	margin-left: auto;
	margin-right: auto;
	width: 40%;
}

Code Example 3

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

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