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

Code Example 1{display:block;margin:auto;width:50%;}{text-align:center;}

Code Example 2

<!--center text-->
<!DOCTYPE html>
.center {
  text-align: center;
  border: 3px solid green;

<h2>Center Text</h2>

<div class="center">
  <p>This text is centered.</p>


Code Example 3

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


Code Example 4

  display: table;

  display: table-cell;
  vertical-align: middle;

Code Example 5

img.a {
  vertical-align: baseline;

img.b {
  vertical-align: text-top;

img.c {

    vertical-align: text-bottom;

img.d {
    vertical-align: sub;

img.e {
  vertical-align: super;

Code Example 6

/**************** 1º method to center all elements ********************/
body {                   
  text-align: center;

/* If all of your elements have the property display equal to "inline", 
"block" or "inline-block", then you can use the text-align: center in
the <body> tag */

tag_name {
    display: inline; /* block or inline-block*/

/*...but if we have an element of type "block" with a width diferente
from the default (maximum width of the page), then this will no 
longer work!*/
tag_name {
    display: block;
  	width: 170px;

/**************** 2º method to center all elements ********************/
/* Another method, is to use the margins to center the element 
horizontally and/or vertically */

tag_name {
    display: block;
  	width: 100px;
  	margin: 0 auto 0 auto;  /* top, right, bottom, left */

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