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HTML

              
                <canvas id="surface"></canvas>

              
            
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CSS

              
                
              
            
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JS

              
                //Configure canvas
var canvas = document.getElementById('surface')
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
//Get canvas context
var ctx = canvas.getContext('2d')
var particles = []
//The greater this number, the more dazzling, and resource-hungry, this animation will become
var maxParticles = 2200

//Various green hues that can Particles can be
var green = ['#2ECC71', '#58D68D', '#239B56', '#48C9B0', '#117A65', '#239B56', '#82E0AA', '#52BE80']

function init() {
  //Generate Particles up until the limit
  for(var i = 0; i < maxParticles; i++) {
    particles.push(new Particle())
  }
}

/**
 * Extend array with a method to return a random member
 *
 * @return {Mixed} A random value from the array
 */
Array.prototype.random = function(){
  return this[Math.floor(Math.random() * this.length)]
}

/**
 * Returns a random number that occurs between the min and max arguments
 *
 * @param  {Number} min The lower bound of the range
 * @param  {Number} max The upper bound of the range
 * @return {Number}     The
 */
function getRandomNumberBetweenRange(min, max) {
  return (Math.floor(Math.random() * (max - min + 1) + min));
}

/**
 * A single transiting datagram
 */
class Particle {
 constructor() {
  this.init()
 }
 //On instantiation, assign y coordinates, lateral velocity, particle size, and color, all at random
 init() {
  this.x = 0,
  this.y = getRandomNumberBetweenRange(100, 400),
  this.vx = getRandomNumberBetweenRange(1, 40),
  this.radius = getRandomNumberBetweenRange(1, 5),
  this.color = green.random()
 }
 //Draws the Particle according to its current properties
 render() {
  ctx.beginPath()
  ctx.arc(this.x, this.y, this.radius, 0, Math.PI * 2, true)
  ctx.closePath()
  ctx.fillStyle = this.color
  ctx.fill()
 }
 //Convenience method for determining if a Particle is off-screen
 timeToReset() {
  return this.x > canvas.width
 }
}

function update() {
  //Wipe entire canvas
  ctx.fillStyle = 'rgba(0, 0, 0, 0.3)' //black background, with slight opacity to generate streaking effect
  ctx.fillRect(0, 0, canvas.width, canvas.height)
  particles.forEach((p) => {
    //If the particle has already transited across
    //the screen, reset its x coordinate to some random position to the left of the viewport
    if (p.timeToReset()) {
      p.x = getRandomNumberBetweenRange(-100, 0)
    } else {
      p.x += p.vx
    }
    p.render()
  })
  window.requestAnimationFrame(update)
}

init();
//Commence matrix-y packet streaming
window.requestAnimationFrame(update)
              
            
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999px

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