I changed the length-value in style.css, because the actual value is too short. Secondly, style switching to ‘uppercase’ in submenu titles is not good, I would change it to ‘none’, as it doesn’t look good in German, if every 1st letter is written uppercase.
And thirdly, there is a bug in displaying long (sub)menus on Tablets, e.g. iPads. The submenus are generated to the right hand side. If you have larger amounts of menu entries, the submenus are displayed out of the screen area and cannot be reached. In these cases, the menus must be displayed to the left side.