neumorphism Icon with Click invert

neumorphism Icon 1.dart

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:payment_app/constants.dart';

void main() {
  //SystemChrome.setEnabledSystemUIOverlays([]);
  return runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: Scaffold(
        backgroundColor: mC,
        body: MainCard(),
      ),
    );
  }
}

class MainCard extends StatefulWidget {
  @override
  _MainCardState createState() => _MainCardState();
}

class _MainCardState extends State<MainCard> {
  bool firstIconClicked = false;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: EdgeInsets.symmetric(horizontal: 16, vertical: 80),
      child: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            GestureDetector(
              onTap: () {
                setState(() {
                  firstIconClicked = !firstIconClicked;
                });
              },
              child: NMButton(
                down: firstIconClicked,
                icon: Icons.arrow_back,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class NMButton extends StatelessWidget {
  final bool down;
  final IconData icon;
  NMButton({this.down, this.icon});

  @override
  Widget build(BuildContext context) {
    return Container(
      width: 100,
      height: 100,
      child: Icon(
        icon,
        size: 50,
        color: down ? fCD : fCL,
      ),
      decoration: down ? kDecoIconClicked : kDecoIconNotClicked,
    );
  }
}


Color mC = Colors.grey.shade100;
Color mCL = Colors.white;
Color mCD = Colors.black.withOpacity(0.075);
Color mCC = Colors.green.withOpacity(0.65);
Color fCD = Colors.grey.shade700;
Color fCL = Colors.grey;

BoxDecoration kDecoIconClicked = BoxDecoration(
  borderRadius: BorderRadius.circular(15),
  color: mCD,
  boxShadow: [
    BoxShadow(
      color: mCL,
      offset: Offset(3, 3),
      blurRadius: 3,
      spreadRadius: -3,
    ),
  ],
);

BoxDecoration kDecoIconNotClicked = BoxDecoration(
  borderRadius: BorderRadius.circular(15),
  color: mC,
  boxShadow: [
    BoxShadow(
      color: mCD,
      offset: Offset(10, 10),
      blurRadius: 10,
    ),
    BoxShadow(
      color: mCL,
      offset: Offset(-10, -10),
      blurRadius: 10,
    )
  ],
);