Long Main Menus cause long black box #74
Description
If a main menu dropdown has many items (even if they are not visible in 'desktop mode') the bottom of the page gets lengthened causing the bottom black to extend.
It's caused by the menu being hidden by css to the left of the visible page by
.js .campl-local-navigation li ul { left:9999px }
but it doesn't move it vertically out of the way causing the problem
see http://sqm.damtp.cam.ac.uk/ and scroll to bottom of page to see the issue.