I’m trying to CSS validate my site and I got a few errors mostly like :
Property text-shadow doesn't exist in CSS level 2.1 but exists in [css2, css3] : 0 1px #393939
The text-shadow is displayed in all tested browsers (FF, Chrome, IE, Opera) but I’d really like my site to pass the CSS validation. How can I fix these errors?
Another error is :
Unknown pseudo-element or pseudo-class :nth-child
which is used to change the table row background color, here’s the corresponding stylesheet line (Blueprint CSS framework) :
You are using some CSS3 there, so there’s no way it will ever validate as CSS2. As Victorinox said, you can validate against CSS3 rules instead.
Don’t get too caught up on validation, though. It’s just a guide to possible mistakes that might break your layouts, rather than a measure of your worth as a designer (or whatever). If, for example, you are using a few hacks for IE that don’t validate, it’s not a problem: the point is that you did this on purpose for a specific reason. Validation is for alerting you to things your weren’t aware of.