Lightbox Form Confirmation text not displaying

Site URL: https://amitybrew.co

Hi all, wondering if anyone can help.

May be a Safari only issue, but when using the Slide animation, the confirmation text within the Form Lightbox function isn't showing.

Does anyone have any knowhow of how to either disable the animation just for this section, or how else to make the text display?

If I turn the animation off site-wide, the text shows, so I know it's down to this! However, I'd prefer to keep animation on site-wide.

Any help very much appreciated. 

It's displaying for me, but I don't have anything with safari to test on.