There is a mistake in the alt attribute which you used for adding images into your CatPhotoApp. You need not add a separate tag for adding the alt text.
Instead, you add it in the img tag itself as an attribute. Did you notice that after your image the code you used was seen as text?
That’s because there is no tag named <alt> and it is only an attribute.
Just add it to the img take like you add the src attribute with the suitable text inside strings.