Fluid image resizing in CSS (or JS?)

I'm trying to show a fairly large image on a page on my site. I want it to be re-sized dynamically depending on the user's resolution, so t开发者_运维百科hat it takes up the same percentage of screen on every monitor. How would I do that?

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Set image width to a percentage.

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Use the percentage values rather than pixels:

<img src="path here" width="100%" />