Check out example codes for "css center text in div vertically". It will help you in understanding the concepts better.

Code Example 1

.center {
  padding: 70px 0;
  border: 3px solid 
green;
  text-align: center;

}

Code Example 2

<!--center text-->
<!--padding deals with margins within the element itself-->
<!--margin deals with blank space surrounding and element-->
<!DOCTYPE html>
<html>
<head>
<style>
.center {
  margin: auto;
  width: 80%;
  border: 3px solid #73AD21;
  padding: 10px; 
  margin: 20px;
}
</style>
</head>
<body>

<h2>Center Align Elements</h2>
<p>To horizontally center a block element (like div), use margin: auto;</p>

<div class="center">
  <p><b>Note: </b>Using margin:auto will not work in IE8, unless a !DOCTYPE is declared.</p>
</div>

</body>
</html>

Code Example 3

<!DOCTYPE html>
<html>
   <head>
      ...
      <style type="text/css">
         div{
         width: 200px;
         height: 200px;
         border: solid green;
         display: table-cell;
         vertical-align: middle;
         }
      </style>
   </head>
   <body>
      <div>Vertikal ausgerichteter Text</div>
   </body>
</html>

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