#top-menu li ul.sub-menu{min-width:280px;width:auto;white-space:nowrap;max-height:400px;overflow-y:auto;overflow-x:hidden;z-index:9999}#top-menu li ul.sub-menu::-webkit-scrollbar{width:6px}#top-menu li ul.sub-menu::-webkit-scrollbar-thumb{background-color:#888;border-radius:4px}#top-menu li ul.sub-menu::-webkit-scrollbar-thumb:hover{background-color:#555}