Theme is provided with a special menu functionality as the header of the theme is designed to be always of the same height. This was also achieved with special menu which will only fit in as many links as possible on the current screen while user is prevented from setting it manually. Which would be anyway impossible while keeping the theme fully responsive.
What happens with remaining links which could not fit?
When screen gets more narrow, also more links would be hidden. But those links are always available in the one drop-down which is compatible with children and megamenus of those links. Drop-down is appropriately represented for the user to be informed that there are more links in the menu.