<img
  src="clairiere.jpg"
  srcset="clairiere-480w.webp 480w, clairiere-800w.webp 800w"
  sizes="(max-width: 480px) 100vw, (max-width: 800px) 50vw, 800px"
  alt="Une clairière verdoyante"
  loading="lazy"
/>