Simple PHP program for beginners

Make a pyramid with asterisk (*) in PHP

<?php
  $height = 3;
  $extraStar = 1;
  
  for($i=1; $i<=$height; $i++){
    for($j=$i; $j<=$height-1; $j++){
      echo "&nbsp;";
    }
    for($k=1; $k<=$i; $k++){
      echo "*";
    }
    for($l=$extraStar; $l>1; $l--){
      echo "*";
    }
    echo "<br/>";
    $extraStar++;
  }
?>