Header Tags on Mobile

Hi friends.

So I added a style to put text shadow and a transparent white background behind the h1 tags on mobile because it’s hard to read the text with the image behind it.

On my desktop version with my browser scaled down I can see this update.
On native mobile (iPhone) it’s the featured image replacing the video, and for some reason the h1 targeting that works on desktop does not work on mobile.

Any ideas what’s happening here or how to target the <h1> tag for the mobile to set the same as it does on desktop?

Thanks!

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