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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              body {
  font-family: Arial, Helvetica, "Liberation Sans", FreeSans, sans-serif;
  background-color: #000;
  margin:0;
  padding:0;
  border-width:0;
}
            
          
!
            
              "use strict";

/**
 * Written by Dillon https://codepen.io/Dillo
 *
 * Inspired in very large part by Alex Andrix's work on Codepen
 * https://codepen.io/alexandrix/pen/jgyWww
 * @author Alex Andrix <alex@alexandrix.com>
 * @since 2019
 */



  const nbEddies = 5;
  const nbParticles = 1000; // number of particles
  const lifeTime = 1000; // average lifetime of particles

  let canv, ctx;   // canvas and drawing context
  let maxx, maxy;  // size of client Window
  let dimx, dimy;  // size of canvas

  let eddies;      // array of eddies
  let particles;   // array of particles

  let requestID;   // ID provided by window.requestAnimationFrame();
  let hueShift;

/* shortcuts for Math */

  const mrandom = Math.random; // see above alternative function for reproductible results
  const mfloor = Math.floor;
  const mround = Math.round;
  const mceil = Math.ceil;
  const mabs = Math.abs;
  const mmin = Math.min;
  const mmax = Math.max;

  const mPI = Math.PI;
  const mPIS2 = Math.PI / 2;
  const m2PI = Math.PI * 2;
  const msin = Math.sin;
  const mcos = Math.cos;
  const matan2 = Math.atan2;
  const mexp = Math.exp;

  const mhypot = Math.hypot;
  const msqrt = Math.sqrt;

//-----------------------------------------------------------------------------
// miscellaneous functions
//-----------------------------------------------------------------------------

  function alea (min, max) {
// random number [min..max[ . If no max is provided, [0..min[

    if (typeof max == 'undefined') return min * mrandom();
    return min + (max - min) * mrandom();
  }

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

  function intAlea (min, max) {
// random integer number [min..max[ . If no max is provided, [0..min[

    if (typeof max == 'undefined') {
      max = min; min = 0;
    }
    return mfloor(min + (max - min) * mrandom());
  } // intAlea

//------------------------------------------------------------------------
function createEddy () {

  return {
   x: alea (dimx),
   y: alea (dimy), 
/*    
   x: dimx / 2,
   y: dimy / 2, 
*/   
//   coeffR: 0.0,        // coefficient for radial velocity
   coeffR: 0.001 * (alea(0.7, 1.3)),        // coefficient for radial velocity
   radius: 150 + alea(-50, 50),          // radius where angular velocity is max
   coeffA1: 10000 * alea(0.8, 1.2),         // coefficient in exponent for angular velocity
   coeffA2: 0.01 * alea(0.8, 1.2),       // multiplying coefficient for angular velocity
   dir: (mrandom() > 0.5) ? 1 : -1 // direction of rotation
   }

} // createEddy

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
function createEddies() {
  eddies = [];                  // create empty array;
  for (let k = 0; k < nbEddies; ++k) {
    eddies.push(createEddy());
  } // for k
} // createEddies

//------------------------------------------------------------------------
function createParticle() {

  return {
    x: alea (-100, dimx + 100),
    y: alea (-100, dimy + 100),
    sat:  `${intAlea(50, 101)}%`,
    light: `${intAlea(30, 80)}%`,
    TTL: alea(lifeTime * 0.8, lifeTime * 1.2) // time to live
  }
} // createParticle
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
function createParticles() {
  particles = [];                  // create empty array;
  for (let k = 0; k < nbParticles; ++k) {
    particles.push(createParticle());
  } // for k
  particles.forEach (part => {
    part.TTL = intAlea(lifeTime); // to avoid too many deaths / births in firts generations
  });
} // createParticles

//------------------------------------------------------------------------
function move() {

  let part, prev, dx, dy, s, c, r, rv, av, deltar;
  let mindeltar;
  
  for (let k = 0; k < nbParticles; ++k) {
    part = particles[k];
// death and re-birth
    if (part.TTL <= 0) {
      part = createParticle();
      particles[k] = part;
    }

    prev = {x: part.x, y: part.y}; // position before this move
    mindeltar = 10000; // used to evaluate hue
    
    eddies.forEach ((eddy, ke) => {
      dx = prev.x - eddy.x;
      dy = prev.y - eddy.y;
      r = mhypot(dx, dy);    // distance particle - centre of the eddy

      if (r < 0.001) r = 0.001;
      s = dy / r; // sine of angle
      c = dx / r; // cosine of angle
      
// angular velocity
      deltar = r - eddy.radius;
      av = eddy.coeffA2 * mexp (- deltar * deltar / eddy.coeffA1) * eddy.dir;
// radial velocity
      rv = - deltar * eddy.coeffR;
      
      part.x += rv * c -  av * r * s;
      part.y += rv * s +  av * r * c;
      
    }) // (loop on eddies)
    --part.TTL; // decrease time to live
// draw it
    let speed =mhypot (prev.x - part.x, prev.y - part.y) ;
    let hue = mmin (speed * 100, 300); // hue based on speed
    hue = (hue + hueShift) % 360;
    ctx.beginPath();
    ctx.moveTo (prev.x, prev.y);
    ctx.lineTo (part.x, part.y);
    ctx.strokeStyle = `hsl(${hue},${part.sat},${part.light})`;
    ctx.stroke();

  } // for k (loop on particles)
} // move

//------------------------------------------------------------------------

//------------------------------------------------------------------------

function startOver() {

// canvas dimensions

  maxx = window.innerWidth;
  maxy = window.innerHeight;

  dimx = maxx - 8; // for a small margin around the canvas
  dimy = maxy - 8; // for a small margin around the canvas

  canv.style.left = (maxx - dimx) / 2 + 'px';
  canv.style.top = (maxy - dimy) / 2 + 'px';

  canv.width = dimx;
  canv.height = dimy;
  
  ctx.lineWidth = 1.5;
  ctx.imageSmoothingEnabled = false;

  hueShift = intAlea(360);
  createEddies();
  createParticles();

  if (typeof requestID == 'number') window.cancelAnimationFrame(requestID);
  (function animate () {
    move();
    requestID = window.requestAnimationFrame(animate);
  })();

} // startOver

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

function clickCanvas() {
  startOver();
}
//------------------------------------------------------------------------
//------------------------------------------------------------------------
// beginning of execution

  {
    canv = document.createElement('canvas');
    canv.style.position = "absolute";
    canv.addEventListener('click',clickCanvas);
    document.body.appendChild(canv);
    ctx = canv.getContext('2d');

  } // canvas creation

  startOver();

  window.addEventListener('resize',startOver);


            
          
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