HTML tag to have image dynamically adjust to fill screen?

I am learning how to make a slideshow presentation wi开发者_开发知识库th S5, and it allows the insertion of images via standard HTML tags.

For slideshows, it is often useful to have a background image that fills the screen during the presentation. Is there a way, such as a HTML tag, that specifically adjusts an image to fill the screen?

Thanks.

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If you are talking about the theme of the S5 slideshows, see pretty.css at http://meyerweb.com/eric/tools/s5/filemap.html There are a number of other themes provided on the site. Have you looked at these?