CENTER TABLE USING FLEX
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<!DOCTYPE html>
<html lang="en">
<head>
 <title>HTML </title>
 <style>
    body{
	  margin: 0;
	  height: 100vh;
	  width: 100vw;
	  display: flex; /* WIDTH and HEIGHT are required*/
	  justify-content: center; /* center the table horizontally*/
	 }
	 .container {
	   position: relative;
	 }
	 .table {
	   position: absolute;
	 }
	
 </style>
</head>

<body>
   <div class="container">
	  <h2 style="text-align: center"> Center the table </h2>
	  
	  <table border>
		<tr>
		  <th>ABC</th>
		  <th>ABC</th>
		  <th>ABC</th>
		  <th>ABC</th>
		</tr>
		<tr>
		  <td>Item 1</td>
		  <td>Item 2</td>
		  <td>Item 3 </td>
		  <td>item 4</td>
		</tr>
		<tr>
		  <td>Item 1</td>
		  <td>Item 2</td>
		  <td>Item 3</td>
		  <td>Item 4</td>
		</tr>
		
	  </table>
  </div>
</body>

</html>