Browsers are free to render things differently, which always makes it difficult for cross browser sites. A CSS reset might be what you need, to reset the base styles for the browser. See http://sixrevisions.com/css/css-tips/css-tip-1-resetting-your-styles-with-css-reset/ for a good description of this problem, and http://meyerweb.com/eric/tools/css/reset/ for the most commonly used reset stylesheet.