Anyone who writes CSS will appreciate note. Apple’s Safari FAQ page for developers lists this note regarding supported CSS properties. Note the language in the last sentence. 😉
16. What CSS properties are supported in Safari?
Safari is designed to provide the most complete implementation of the CSS specification. There are however, some CSS properties that are not available or only partially implemented. If your site is utilizing CSS that doesn’t appear to work in Safari, please review this list as a sanity check.