npm install --save particles-bg

import React, { Component } from 'react'

import ParticlesBg from 'particles-bg'

class Example extends Component {
  render () {
    return (
      <>
        <div>...</div>
        <ParticlesBg type="circle" bg={true} />
      </>
    )
  }
}

<ParticlesBg color="#ff0000" num={200} type="circle" bg={true} />

"color"
"ball"
"lines"
"thick"
"circle"
"cobweb"
"polygon"
"square"
"tadpole"
"fountain"
"random"
"custom"

position: "absolute",
zIndex: -1,
top: 0,
left: 0

  let config = {
      num: [4, 7],
      rps: 0.1,
      radius: [5, 40],
      life: [1.5, 3],
      v: [2, 3],
      tha: [-40, 40],
      // body: "./img/icon.png", // Whether to render pictures
      // rotate: [0, 20],
      alpha: [0.6, 0],
      scale: [1, 0.1],
      position: "center", // all or center or {x:1,y:1,width:100,height:100}
      color: ["random", "#ff0000"],
      cross: "dead", // cross or bround
      random: 15,  // or null,
      g: 5,    // gravity
      // f: [2, -1], // force
      onParticleUpdate: (ctx, particle) => {
          ctx.beginPath();
          ctx.rect(particle.p.x, particle.p.y, particle.radius * 2, particle.radius * 2);
          ctx.fillStyle = particle.color;
          ctx.fill();
          ctx.closePath();
      }
    };

    return (
      <div>
        <SignIn />
        <ParticlesBg type="custom" config={config} bg={true} />
      </div>
    )