Span

Hi Silvia!

The span is wrapped around the img simply to provide a reference for the original position of the img. If we apply the "original-pos" class to the img, the transforms we apply to the img will also be applied to the "original-pos" class. We can see this in action by adding a red border to the "original-pos" class and moving the class from a span to the img element:

.original-pos {
    background-color: lightgrey;
    height: 100%;
  + border: 2px solid red;
    display: block;
    line-height: 0;
}

<img + class="original-pos" src="img/photos/1.jpg" alt="Big Sur">

With these changes applied, you can see that the first image has a red border while the second and third image just have the red border surrounding the span behind them. Using a span around the img element just ensures it has the same dimensions and position as the element it surrounds. Then we can target the two elements separately in CSS. I hope this helps!

Happy coding! :)