lazyload-datuan.js

if ('loading' in document.createElement('img')) {
    document.querySelectorAll('[loading="lazy"]').forEach(elem => {
        if (elem.dataset.src) {
            elem.src = elem.dataset.src;
        }
        if (elem.dataset.srcset) {
            elem.srcset = elem.dataset.srcset;
        }
    })
} else {
    document.querySelectorAll('[loading=lazy]').forEach(elem => {
        elem.classList.add("lazyload");
    })

    var script = document.createElement('script');
    script.onload = function () {
        const el = document.querySelectorAll('img[data-src]');
        const observer = lozad(el);
        observer.observe();
    };
    script.src = 'https://cdnjs.cloudflare.com/ajax/libs/lozad.js/1.16.0/lozad.min.js';
    document.head.appendChild(script);
}