img { max-width: 100%; height: auto; }
.img-sm { width: 320px; } .img-md { width: 560px; } .img-lg { width: 800px; }
p > img:only-child { display: block; margin: 0.75rem auto; }
.yt-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; margin: 1rem 0; }
.yt-container iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }

.is-embed .md-footer .md-footer-meta {
    display: none;
}