style
fun style(cellShape: OtpCellShape = OtpCellShape.Box, cellSize: Dp = when (LocalFormFactor.current) {
FormFactor.Watch -> 28.dp
FormFactor.Tv -> 64.dp
FormFactor.Handheld, FormFactor.Desktop -> 48.dp
}): OtpFieldStyle
Every colour comes from MaterialTheme.colorScheme — this module ships no palette, so the consumer's theme decides what "error" and "active" look like. The source idiom hardcoded Color.Blue / Color.Black / Color.Gray / Color.Red, which is invisible in dark mode.
Cell size follows the surface: a wrist cannot fit six 48dp boxes, and a 48dp box is unreadable from a sofa.