Layout Engines, Browser Types, and CSS Version Support

Layout Engine         Browser System                  Supports CSS Version

Gecko                   Mozilla Firefox                    CSS v1, v2, v3 (partially) *

Presto                    Opera                              CSS v1, v2, v3 (partially) *

Trident                  Internet Explorer              CSS v1, v2, v3 (slightly) *

WebKit                   Google Chrome, Safari         CSS v1, v2, v3 (partially) *

*Partially and slightly indicate that the layout engines listed don’t fully support CSS v3, at this time. Partial support indicates that the layout engine understands CSS v3 properties, but they aren’t supported entirely. Slight support indicates that the layout engine is understood by the browser, but support is incomplete, and at times, buggy.

 The absolute best way to test your Web site across the various browser sys-

tems is to download the browser to your computer and then load your Web
site in it, checking for correct rendering as you go. However, if you only have
a Windows computer, you can’t really test your Web site on a Mac, and vice
versa. Don’t fret, though, because here are two alternatives for you: