Plugin Development/ Stop CSS clashes.

If you don’t know, and can’t control, the content width, then your Plugin shouldn’t assume any given content width.

Also, even though templates may be 960px in total width, the content width will almost assuredly be less than that.

If you must apply explicit width to your output, you could try returning the value set for the $content_width global, and then use that value in your generated CSS.