code: function( elem, options, callback ) {
  		var old = {};
  
  		// Remember the old values, and insert the new ones
  		for ( var name in options ) {
  			old[ name ] = elem.style[ name ];
  			elem.style[ name ] = options[ name ];
  		}
  
  		callback.call( elem );
  
  		// Revert the old values
  		for ( var name in options ) {
  			elem.style[ name ] = old[ name ];
  		}
  	}
docs: A method for quickly swapping in/out CSS properties to get correct calculations