Add current user role to the body class

add_role_to_body_class.php

<?php

add_filter( 'body_class', 'add_role_to_body_class' );

function add_role_to_body_class( $classes ) {
  // Get the current user's roles
  $user_roles = wp_get_current_user()->roles;

  // Loop through the roles and add them to the body class
  foreach ($user_roles as $role) {
    $classes[] = $role . '-role';
  }

  // Return the modified classes
  return $classes;
}