// ---- Performance: Lazy Loading for images and iframes ----
add_action('wp_footer', function() {
    echo '<script>document.addEventListener("DOMContentLoaded",function(){document.querySelectorAll("img:not([loading])").forEach(function(img){if(img.getBoundingClientRect().top>window.innerHeight*0.5){img.loading="lazy";}});document.querySelectorAll("iframe:not([loading])").forEach(function(f){f.loading="lazy";});});<\/script>';
});