Test if a browser supports a CSS selector

Question

Really simple: how do I most accurately test if a browser has support for a certain CSS selector?

I currently have some CSS code that makes the page a little more in

Answer 1

Workaround for your case:

css:

input{
  font-family:'arial';
}
input:checked{
  font-family:'sans-serif';
}

checking procedure: js

alert($('input').css('font-family')=='sans-serif'?'supported':'not supported');