How can i add class within menu ul -> "li" tag?

Here we’ll add “col-eye” class within “li” tag

Output:

<ul>
    <li class="col-eye"><a href="#">Lorem ipsam amit</a></li>
    <li class="col-eye"><a href="#">Lorem ipsam amit</a></li>
    <li class="col-eye"><a href="#">Lorem ipsam amit</a></li>
<ul>

Input:

<ul>
<?php
echo preg_replace( '#<li[^>]+>#', '<li class="col-eye">',
  wp_nav_menu(
     array(
        'menu' => $nav_menu,
        'container' => false,
        'container_class' => false,
        'menu_class' => false,
        'items_wrap' => '%3$s',
        'depth' => 1,
        'echo' => false
     )
  )
);
?>
</ul>