Menu disappears off screen at 3rd level

I'm having an issue with the dropdown navigation in the High Responsive Free theme. My Menu is fairly extensive, and when I'm on a laptop the third level of navigation disappears off screen to the right of the far right dropdown. On mobile this is not an issue, as the menu stacks nicely. Is there a way to have the menu expand to the left instead of the right when it hits the edge? Thanks! I love this theme!