isotope error on page load

isotope error on page load


I've been searching high and low and there is still no answer for this.

I building an isotope, and i want to show 'artwork' tab on page load, but it's not working.

sample URL: http://test.melvintee.com/testing.html

Code: 
 $(document).ready(function () {  $grid.isotope({ filter: '.artwork' }); });

filter by artwork is not working on page load. you can view my source, the code above i already insert.

Can anyone give me an advice?

Thanks