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CSS

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JavaScript

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HTML 

              
                <canvas id="view"></canvas>

<aside style="display:none">
  <img id="star-texture" src="https://s3-us-west-2.amazonaws.com/s.cdpn.io/106114/stars-02.png?v=1">
</aside>

<div id="quick-settings"></div>
!

CSS 

              
                body {
  background: #111;
  touch-action: none;
}

#view {
  position: fixed;
  top: 0;
  left: 0;
  visibility: hidden;
}

#quick-settings {
  position: fixed;
  top: 5px;
  right: 170px;
  right: 205px;
}
!

JS 

              
                console.clear();
const log = console.log.bind(console);

const TAU = Math.PI * 2;

//
// PARTICLE
// ===========================================================================
class Particle {
  
  alive = false;  
  
  constructor(public texture, public frame) {   
    this.width = frame.width;
    this.height = frame.height;
    this.originX = frame.width / 2;
    this.originY = frame.height / 2;
  }
  
  init(x = 0, y = 0) {
    
    const angle = random(TAU);
    const force = random(2, 6);
    
    this.x = x;
    this.y = y;
    this.alpha = 1;
    this.alive = true;
    this.theta = angle; 
    this.vx = Math.sin(angle) * force;
    this.vy = Math.cos(angle) * force;    
    this.rotation = Math.atan2(this.vy, this.vx);    
    this.drag = random(0.82, 0.97);    
    this.scale = random(0.1, 1);
    this.wander = random(0.5, 1.0);    
    
    this.matrix = { a: 1, b: 0, c: 0, d: 1, tx: 0, ty: 0 };
    
    return this;
  }
  
  update() {
    
    const matrix = this.matrix; 
    
    this.x += this.vx;
    this.y += this.vy;
    this.vx *= this.drag;
    this.vy *= this.drag;
    
    this.theta += random(-0.5, 0.5) * this.wander;
    
    this.vx += Math.sin(this.theta) * 0.1;
    this.vy += Math.cos(this.theta) * 0.1;
    
    this.rotation = Math.atan2(this.vy, this.vx);
    
    this.alpha *= 0.98;
    this.scale *= 0.985;
    this.alive = this.scale > 0.06 && this.alpha > 0.06;
       
    const cos = Math.cos(this.rotation) * this.scale;
    const sin = Math.sin(this.rotation) * this.scale;
        
    matrix.a =  cos;
    matrix.b =  sin;
    matrix.c = -sin;
    matrix.d =  cos;
    matrix.tx = this.x - ((this.originX * matrix.a) + (this.originY * matrix.c));
    matrix.ty = this.y - ((this.originX * matrix.b) + (this.originY * matrix.d));
        
    return this;
  }
  
  draw(context) {
    
    const m = this.matrix;
    const f = this.frame;
    
    context.globalAlpha = this.alpha;
    context.setTransform(m.a, m.b, m.c, m.d, m.tx, m.ty);
    context.drawImage(this.texture, f.x, f.y, f.width, f.height, 0, 0, this.width, this.height);
    
    return this;
  }
}


//
// APP
// ===========================================================================
class App {
   
  pool = [];
  particles = [];
  
  pointer = {
    x: -9999,
    y: -9999
  };
  
  buffer = document.createElement("canvas");
  bufferContext = this.buffer.getContext("2d");
  supportsFilters = (typeof this.bufferContext.filter !== "undefined");
   
  constructor(options) {
    
    Object.assign(this, options);    
    this.context = this.view.getContext("2d", { alpha: false });    
  }
    
  pointerMove = event => {
    
    event.preventDefault();

    const pointer = event.targetTouches ? event.targetTouches[0] : event;
    
    this.pointer.x = pointer.clientX;
    this.pointer.y = pointer.clientY;
    
    for (let i = 0; i < random(2, 7); i++) {
      this.spawn(this.pointer.x, this.pointer.y);
    }
  }
  
  resize = event => {    
    this.width = this.buffer.width = this.view.width = window.innerWidth;
    this.height = this.buffer.height = this.view.height = window.innerHeight;
  }
  
  render = time => {
    
    const context = this.context;
    const particles = this.particles;    
    const bufferContext = this.bufferContext;
    
    context.fillStyle = this.backgroundColor;
    context.fillRect(0, 0, this.width, this.height);
    
    bufferContext.globalAlpha = 1;
    bufferContext.setTransform(1,0,0,1,0,0);
    bufferContext.clearRect(0, 0, this.width, this.height);
    bufferContext.globalCompositeOperation = this.blendMode;
        
    for (let i = 0; i < particles.length; i++) {
      const particle = particles[i];

      if (particle.alive) {
        particle.update();
      } else {
        this.pool.push(particle);        
        removeItems(particles, i, 1);
      }
    }   
    
    for (let particle of particles) {    
      particle.draw(bufferContext);
    }
    
    if (this.supportsFilters) {
      
      if (this.useBlurFilter) {
        context.filter = `blur(${this.filterBlur}px)`;  
      }
      
      context.drawImage(this.buffer, 0, 0); 
      
      if (this.useContrastFilter) {
        context.filter = `drop-shadow(4px 4px 4px rgba(0,0,0,1)) contrast(${this.filterContrast}%)`; 
      }                 
    }
    
    context.drawImage(this.buffer, 0, 0);
    context.filter = "none";
                
    quickSettings.setValue("Particles", `
      Active = ${this.particles.length}<br>
      Cached = ${this.pool.length}`
    );
    
    requestAnimationFrame(this.render);
  }
  
  spawn(x, y) {
          
    let particle;
    
    if (this.particles.length > this.maxParticles) {
      particle = this.particles.shift();
    } else if (this.pool.length) {
      particle = this.pool.pop();
    } else {
      particle = new Particle(this.texture, sample(this.frames));
    }
    
    particle.init(x, y);    
    this.particles.push(particle);
    return this;
  }
  
  start() {
    
    this.resize();
    this.render();
    this.view.style.visibility = "visible";
        
    if (window.PointerEvent) {      
      window.addEventListener("pointermove", this.pointerMove);      
    } else {      
      window.addEventListener("mousemove", this.pointerMove);
      window.addEventListener("touchmove", this.pointerMove);
    }
    
    window.addEventListener("resize", this.resize);
    requestAnimationFrame(this.render);
    return this;
  } 
}

//
// CREATE FRAMES
// ===========================================================================
function createFrames(numFrames, width, height) {
  
  const frames = [];
  
  for (let i = 0; i < numFrames; i++) {
    
    frames.push({
      x: width * i,
      y: 0,
      width: width,
      height: height
    });
  }
  
  return frames;
}

//
// REMOVE ITEMS
// ===========================================================================
function removeItems(array, startIndex, removeCount) {
  
  const length = array.length;

  if (startIndex >= length || removeCount === 0) {
    return
  }

  removeCount = (startIndex + removeCount > length ? length - startIndex : removeCount)

  const len = length - removeCount

  for (let i = startIndex; i < len; ++i) {
    array[i] = array[i + removeCount]
  }

  array.length = len
}

//
// RANDOM
// ===========================================================================
function random(min, max) {
  if (max == null) { max = min; min = 0; }
  if (min > max) { var tmp = min; min = max; max = tmp; }
  return min + (max - min) * Math.random();
}

function sample(array) {
  return array[(Math.random() * array.length)|0];
}

//
// QUICK SETTINGS
// ===========================================================================
const app = new App({
  view: document.querySelector("#view"),
  texture: document.querySelector("#star-texture"),
  frames: createFrames(5, 80, 80),
  maxParticles: 2000,
  backgroundColor: "#111111",
  blendMode: "lighter",  
  filterBlur: 50,
  filterContrast: 300,  
  useBlurFilter: true,
  useContrastFilter: true
});

const blendModes = [
  { label: "Source Over", value: "source-over" },
  { label: "Source In", value: "source-in" },
  { label: "Source Out", value: "source-out" },
  { label: "Source Atop", value: "source-atop" },
  { label: "Destination Over", value: "destination-over" },
  { label: "Destination In", value: "destination-in" },
  { label: "Destination Out", value: "destination-out" },
  { label: "Destination Atop", value: "destination-atop" },
  { label: "Lighter", value: "lighter" },
  { label: "Copy", value: "copy" },
  { label: "Xor", value: "xor" },
  { label: "Multiply", value: "multiply" },
  { label: "Screen", value: "screen" },
  { label: "Overlay", value: "overlay" },
  { label: "Darken", value: "darken" },
  { label: "Lighten", value: "lighten" },
  { label: "Color Dodge", value: "color-dodge" },
  { label: "Color Burn", value: "color-burn" },
  { label: "Hard Light", value: "hard-light" },
  { label: "Soft Light", value: "soft-light" },
  { label: "Difference", value: "difference" },
  { label: "Exclusion", value: "exclusion" },
  { label: "Hue", value: "hue" },
  { label: "Saturation", value: "saturation" },
  { label: "Color", value: "color" },
  { label: "Luminosity", value: "luminosity" },
];

const blendModeNames = blendModes.map(blendMode => blendMode.label);
const blendModeIndex = blendModes.findIndex(blendMode => blendMode.value === app.blendMode);

const container = document.querySelector("#quick-settings");
const quickSettings = QuickSettings.create(0, 0, "Settings", container)
  .addHTML("Support", `Supports Filters: ${app.supportsFilters}`)
  .hideTitle("Support")
  .addHTML("Particles", "")
  .addBoolean("Blur Filter", app.useBlurFilter, value => {
    app.useBlurFilter = value;
    if (value) {
      quickSettings.showControl("Blur Radius")
    } else {
      quickSettings.hideControl("Blur Radius")
    }
  })
  .addRange("Blur Radius", 0, 200, app.filterBlur, 1, value => app.filterBlur = value)
  .addBoolean("Contrast Filter", app.useContrastFilter, value => {
    app.useContrastFilter = value;
    if (value) {
      quickSettings.showControl("Contrast")
    } else {
      quickSettings.hideControl("Contrast")
    }
  })
  .addRange("Contrast", 0, 400, app.filterContrast, 1, value => app.filterContrast = value)  
  .addDropDown("Blend Mode", blendModeNames, item => app.blendMode = blendModes[item.index].value)
  .addColor("Background", app.backgroundColor, color => app.backgroundColor = color)
  .setValue("Blend Mode", blendModeIndex || 0)

window.addEventListener("load", app.start());
window.focus();

log("APP", app);
!
999px

Console