Display page slug body class

functions.php

<?php
/**
 * Page slug body class
 * https://www.wpbeginner.com/wp-themes/how-to-add-page-slug-in-body-class-of-your-wordpress-themes/
 * 
 */
function add_slug_body_class( $classes ) {

    global $post;
    if ( isset( $post ) ) {
    $classes[] = $post->post_type . '-' . $post->post_name;
    }
    return $classes;

}
add_filter( 'body_class', 'add_slug_body_class' );