3.2.1 CSS W3C compatibility
Like HTML and W3C compatibility, CSS compatibility is important because we can find out if our CSS style is compatible with the browsers.Upload the '02Demo' to your website via ftp and go to the
W3C CSS Validation Service , paste your url and press the check button. You should not find any errors. ('CSS level 2.1'). An alternative CSS validation can be made directly from notepad++ just by pressing TextFx -> TextFx Convert -> Submit to W3C CSS Validator.
fig:12 Alternative CSS Validation
As you can see, if you modify only the values of the given CSS you should always get a valid CSS.