Menu dropdowns disappear off edge of screen

Hi guys,

When third-level menu items are near the edge of the screen, they disappear out of the window’s frame, making them unselectable on tablets and smaller screens. You can see this in the example below:

https://www.burnetnewsclub.com/wp-content/uploads/2015/10/screen-disappear.png

Should the menu detect the width of the screen and come out of the left-hand-side of the dropdown rather than the right in these situations? This problem limits the responsiveness of the theme.

Thanks,
Mike