if you click on a category from this site: http://g.litchd.com/ it'll take you to another set of categories. How are they doing this? I've been searching the whole day and haven't even gotten close to figuring this out. can someone direct me in the right direction? I can add a category as a child to a parent, but it'll list it in the sidebar which i don't want. I only want the child to show only when the parent is clicked.