How to Add an Image to a CSS File. 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.

To check if an image has alt text, try selecting the image with your screen reader on. or manually "Inspect" the image in any browser.

Select this to add alt text to your photo. Twitter alt text has a 1,000-character limit, and you can consult the website's own advice for writing accessible picture description, as well.