Change Css class properties with jQuery
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Is there a way to change a CSS class properties, not the element properties.

Here is a practical example:
I have a div with class 'red'

    .red{background:red;}

I want to change class 'red' background property, not elements that have class 'red' background assigned.

If I do it with simple jquery:

    $('.red').css('background','green');

it will affect the elements that actually have class 'red'. Up to here is fine.
But if I make an Ajax call, and introduce more divs with 'red' class, those won't have a green background, they will have the initial 'red' background.

Of course I could call the simple jquery again. But I would like to know if there is a way to change the class itself (with jquery). (Consider this is just a basic example).

Thanks.