viewportHeight
fun DomposableModifier.viewportHeight(fraction: Float = 1.0f, subtract: DomposableLength = 0.dp, unit: DomposableViewportUnit = DomposableViewportUnit.Dynamic): DomposableModifier
Bounds content using the host viewport, rather than its parent's available height. subtract reserves app-owned chrome. Native uses the current window size for both units; HTML uses dvh/svh. Neither includes additional safe-area padding automatically.