Code:

import 'package:flutter/material.dart';
import 'package:particles_flutter/particles_flutter.dart';

class Background1 extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    double h = MediaQuery.of(context).size.height;
    double w = MediaQuery.of(context).size.width;
    return Scaffold(
      backgroundColor: Colors.redAccent,
      body: CircularParticle(
        width: w,
        height: h,
        awayRadius: w / 5,
        numberOfParticles: 150,
        speedOfParticles: 1.5,
        maxParticleSize: 7,
        particleColor: Colors.white.withOpacity(.7),
        awayAnimationDuration: Duration(milliseconds: 600),
        awayAnimationCurve: Curves.easeInOutBack,
        onTapAnimation: true,
        isRandSize: true,
        isRandomColor: false,
        connectDots: true,
        enableHover: true,
        hoverColor: Colors.black,
        hoverRadius: 80,
      ),
    );
  }
}