Javascript/jQuery expert needed ASAP

Hi, Please look at this page: [login to view URL] The portfolio items are filterable using mixitup jquery plugin. If you used the mixitup plugin before you should know how it works. I want a little customization: You know, whenever I add an item under any category (for example: "Multi-Family"), it shows under "All" category also. But, I want to add 1 item under the "Multi-Family" category, but I don't want that item to be shown in "All" category, it means the new item should be hidden (display:none;) under "All" category and only visible under "Multi-Family" category. Please put "Multi-Family" in the first line of your bid message so that I can understand you read the details carefully. I think I should be able to add a new 'class' (example class name: 'hide-all') for that new item, so that if I use that class for any item, it will be hidden under "All" category. If you are jquery expert, it should take less than 1 hour to complete this project. I need this done asap. Willing to pay $20 for this little task. I will award the project quickly. Thanks