how to center body text in html code example

Example 1: css align center

//HTML
<div class="parent">
	<span>Hello World</span>
</div>

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

Example 2: html center body

body {
  display:flex; flex-direction:column; justify-content:center;
  min-height:100vh;
}

Example 3: html center body

body {
max-width: max-content;
margin: auto;
}