Add ID to Cart Page when Cart Page is Empty

#1. Use code to Code Injection – Footer

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
window.addEventListener("load", (event) => {
    $('p.empty-message').closest('body').addClass('empty-cart-page');
});
</script>

#2. Result