wp support - expandable/collapsible posts - functions.php

<?php
// Exit if accessed directly
if ( !defined( 'ABSPATH' ) ) exit;

// Enqueue parent

if ( !function_exists( 'chld_thm_cfg_parent_css' ) ):
    function chld_thm_cfg_parent_css() {
        wp_enqueue_style( 'chld_thm_cfg_parent', trailingslashit( get_template_directory_uri() ) . 'style.css' );
    }
endif;
add_action( 'wp_enqueue_scripts', 'chld_thm_cfg_parent_css' );


// Enqueue child scripts

function my_scripts_method() {
    wp_enqueue_script(
        'custom-script',
        get_stylesheet_directory_uri() . '/custom.js',
        array( 'jquery' ),
        '1.0',
        true
    );
}

add_action( 'wp_enqueue_scripts', 'my_scripts_method' );