Opening and closing feature of Q&A on mobile of horizontal mode

Hi there,

I have an issue that when I used the mobile phone(in this case which is IPhone6s, IPhone7) in the horizontal mode, my Q&A page will become so weird, the element will jump around. Can you help me to fix it?

example video: https://drive.google.com/open?id=0B0qG2KuE7KSVRU5oR2dxcE9OVEE
Issue page: http://mobilegame.oops.com.tw/faq/