Rounded Video Backgrounds working on Desktop, but not Mobile

Site URL: https://wilda.squarespace.com/

Hi there! So on my current site I'm having an issue where I added a border radius of 30px to the section video backgrounds. It's working perfectly on desktop, but not on my actual mobile device. It seems to render right in the mobile preview, but on my actual iPhone it doesn't work. 

Can someone help me with this? 

Thanks!

https://wilda.squarespace.com/
pass: brineintopedro

video {border-radius: 100px !important;}