You can dynamically add a
block to override it. Give it an id
and you can remove it when needed.
Demo: http://jsfiddle.net/ThinkingStiff/TRLY2/
Script:
$( '#hello' ).click( function () {
if( $( '#pseudo' ).length ) {
$( '#pseudo' ).remove();
} else {
var css = '';
document.head.insertAdjacentHTML( 'beforeEnd', css );
};
} );
HTML:
hello
CSS:
#hello::after {
content: "goodbye";
}