text: import React from 'react';
  import { NavigationContainer } from '@react-navigation/native';
  import { createStackNavigator } from '@react-navigation/stack';
  import { gStyle } from '../constants';
  
  // stacks
  import StackMain from './StackMain';
  
  // screens
  import ChangeVideoBackground from '../screens/ChangeVideoBackground';
  
  const Stack = createStackNavigator();
  
  export default () => (
    <NavigationContainer>
      <Stack.Navigator
        screenOptions={{
          presentation: 'modal'
        }}
      >
        <Stack.Screen
          name="StackMain"
          component={StackMain}
          options={{ headerShown: false }}
        />
        <Stack.Screen
          name="ChangeVideoBackground"
          component={ChangeVideoBackground}
          options={{
            headerTitleStyle: gStyle.navHeaderTitleStyle,
            title: 'Select a Video'
          }}
        />
      </Stack.Navigator>
    </NavigationContainer>
  );
  