Same here, but not only in Safari, but also in other browsers (Firefox, Edge, Chrome). Tested with iPadOS (those are all Safari WebKit subvariants) and macOS (here things should have been better). The floating toggle works flawlessly, yet the plugin does not respond when I switch the overall device theme from light to dark mode.
The site is using the latest WordPress 6.5.5 with Divi theme 4.26.0, MariaDB 10.6 and PHP 8.
Otherwise a great plugin, thank you!