Scrolling issues

Hello,

First, thanks for a great plugin!

Second: I am having issue with scrolling on mobile. If you check out the website URL I provided on mobile (or responsive design mode on desktop), you’ll see that if you click on the menu, and then a category (for example Babyzen), you cannot scroll down. It seems like the page in background (behind the menu) is scrolling, and not the menu itself: thus I cannot view the whole menu.

Could you kindly let me know how to fix this? Thank you very much.

The page I need help with: [log in to see the link]