will-change: transform on a position:relative flex child causes iOS WebKit
to composite the element at an incorrect position - creating a visible gap
below the nav bar. Remove it; CSS transform transitions use hardware
acceleration automatically on modern iOS without this hint.
Add -webkit-fill-available before 100dvh on .app-shell as a fallback for
iOS WebKit versions where 100dvh is computed slightly smaller than the
actual WKWebView height.
Ulas
a7ac7d105c