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

Code Example 1

button{
    /*Change the width as much as you like, but make sure 
    margin-left and margin-right + width = 100%*/
    width:50%;
    margin-left:25%;
    margin-right:25%;
}

Code Example 2

.center {
  display: flex;
  justify-content: center;
  
  align-items: center;
  height: 200px;
  border: 3px solid 
  green; 
}

Code Example 3

<div style="text-align:center;">
    <button>button1</button>
    <button>button2</button>
</div>

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