How to Remove Mobile Theme/Responsiveness on Adelle theme (Urgent)

Hello everyone. I am working on a blog of a friend and she would want to disable mobile themes so that whenever viewers view her blog on a mobile device, it doesn’t adapt on the mobile’s screen size and stays as it is just like how it is seen on desktop views.

Now, I have found out on how to disable mobile responsiveness just by going to Mobile under Appearance. Unfortunately, I cannot seem to find Mobile under Appearance in her blog. (Click here to see photo). I tried logging in to my own account the Mobile option under Appearance is there. My friend is using kawaii.ph domain, which I think is a custom domain(?) She is using the Adelle theme.

Can somebody please help me? I really need help asap.