The backdrop of a cinema hero frame: a video poster fading into the page
background from the left and from the bottom, so copy laid over it reads in
both themes.
Fills its nearest positioned ancestor behind the content (-z-10), so the
frame needs relative isolate. Without a poster it draws a soft glow in the
theme's accent. Purely decorative: hidden from assistive technology.
The backdrop of a cinema hero frame: a video poster fading into the page background from the left and from the bottom, so copy laid over it reads in both themes.