how to center horizonally in html code example

Example 1: centering horizontally

div.center{display:block;margin:auto;width:50%;}
p.center{text-align:center;}

Example 2: how to center align the html element in css examples

#inner {
  width: 50%;
  margin: 0 auto;
}

# center text
.center {
  text-align: center;
  
border: 3px solid green;
}