Web pages normally add images using the inline HTML "img" tag. CSS coding usually doesn't set an image's source because CSS controls design rather than content. Yet CSS supports properties that ...

The image's width will be 400 pixels wide because that's the value defined in the stretchX CSS class. Return to your document and change 400 to any other value to make the image stretch to that width.

Ryan Boudreaux includes all the code snippets you'll need in this demo of how to create an image hover-preview effect using HTML, CSS, and JavaScript.