you have to change it through your wordpress dashboard (if your theme has that option) or modifying your html code 🙂
functions.php line number 260.
My remarks after visiting your site, if you want to have a menu item just as a container for sub-items, create a link menu item (put just # as web address), then, when it is already created, edit it by deleting the link address, this way you will be able to stack other items under it, but you will not have to create an extra page, sometimes it may be confusing for users too.