Changing colour fixed TopAppBar

Scaffold.kt

...
val listState = rememberLazyListState()
val isScrolled = remember { derivedStateOf { listState.firstVisibleItemIndex > 0 } }

val topAppBarContainerColor = if (isScrolled.value) {
    MaterialTheme.colorScheme.surfaceVariant
} else {
    MaterialTheme.colorScheme.surface
}

Scaffold(
    topBar = {
        TopAppBar(
            title = { Text(text = stringResource(id = R.string.title)) },
            navigationIcon = { NavigationIcon(navController = navController)},
            actions = { AboutActionIcon(navController) },
            colors = TopAppBarDefaults.smallTopAppBarColors(
                containerColor = topAppBarContainerColor,
                navigationIconContentColor = MaterialTheme.colorScheme.onSurface,
                actionIconContentColor = MaterialTheme.colorScheme.onSurface,
                titleContentColor = MaterialTheme.colorScheme.onSurface
            )
        )
    },
    modifier = modifier
) { innerPadding ->
    LazyColumn(
        state = listState,
        modifier = Modifier.fillMaxSize().padding(innerPadding)) {
        items(items) { item ->
            ...
        }
    }
}