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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.

            
              <canvas id="stage" width="512" height="512"></canvas>

            
          
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              html, body {
    height: 100%;
}

body {
   display: flex;
   align-items: center;
   justify-content: center;
   background: rgb(5, 26, 50);
}
            
          
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              // Set up canvas
let canvas = document.querySelector('#stage');

// High DPI Canvas
// https://www.html5rocks.com/en/tutorials/canvas/hidpi/
let devicePixelRatio = window.devicePixelRatio || 1;
let ctx = canvas.getContext('2d');
let backingStoreRatio =
    ctx.webkitBackingStorePixelRatio ||
    ctx.mozBackingStorePixelRatio ||
    ctx.msBackingStorePixelRatio ||
    ctx.oBackingStorePixelRatio ||
    ctx.backingStorePixelRatio ||
    1;
let ratio = devicePixelRatio / backingStoreRatio;
let ow = canvas.width;
let oh = canvas.height;
if (devicePixelRatio !== backingStoreRatio) {
   canvas.width = ow * ratio;
   canvas.height = oh * ratio;
   canvas.style.width = ow + 'px';
   canvas.style.height = oh + 'px';
}

ctx.translate(canvas.width / 2, canvas.height / 2);
   ctx.scale(ratio, ratio);

// initial draw
let {width: w, height: h} = canvas;
ctx.strokeStyle = 'rgba(87,225,255,0.01)';
ctx.fillStyle = 'rgba(87,225,255,0.04)';
ctx.lineWidth = 1;
ctx.lineCap = 'round';
ctx.globalCompositeOperation = 'lighter';

let k = 4; // control points to draw a spline
let N = 10;
let rings = 3;
let controlPtsGroups = [];
for (let o = 0; o < rings; o++) {
   // prepare controls point
   let r = ow / 6 + o * ow / 8;
   let controlPts = [];
   let n = N + o * 5;
   for (let i = 0; i < n; i++) {
      let rad = 2 * Math.PI * i / n;
      let x = Math.cos(rad) * r;
      let y = Math.sin(rad) * r;
      controlPts.push([x, y, x, y]); // [cx, cy, ox, oy]
   }
   controlPtsGroups.push(controlPts);
}

// The uniform bspline matrix
// http://graphics.cs.ucdavis.edu/~joy/ecs178/Unit-7-Notes/MatrixBSpline.pdf
let UNIFORM_BSPLINE_MATRIX = math.matrix([
   [1 / 6, 4 / 6, 1 / 6, 0],
   [-3 / 6, 0, 3 / 6, 0],
   [3 / 6, -6 / 6, 3 / 6, 0],
   [-1 / 6, 3 / 6, -3 / 6, 1 / 6],
]);

let SPLINE_SEGMENT = 20;

// render loop
requestAnimationFrame(function loop() {
   for (let o = 0; o < rings; o++) {
      let controlPts = controlPtsGroups[o];
      let n = controlPts.length;
      for (let i = 0; i < n; i += 1) {
          let controlMatrix = math.multiply(UNIFORM_BSPLINE_MATRIX, [
             controlPts[(i + 0) % n],
             controlPts[(i + 1) % n],
             controlPts[(i + 2) % n],
             controlPts[(i + 3) % n],
          ]);
         for (let j = 0; j < 1; j += 1 / SPLINE_SEGMENT) {
            let ts = [1, j, j * j, j * j * j];
            let p = math.multiply(ts, controlMatrix);
            ctx.fillRect(p.get([0]), p.get([1]), 1, 1);
         }
      }
      // spread
      for (let i = 0; i < n; i++) {
         let [cx, cy, ox, oy] = controlPts[i];
         let spread = 1 + Math.sqrt((cx - ox) * (cx - ox) + (cy - oy) * (cy - oy)) / 20;
         controlPts[i][0] += (Math.random() * 2 - 1) * spread;
         controlPts[i][1] += (Math.random() * 2 - 1) * spread;
      }
   }
   requestAnimationFrame(loop);
});
            
          
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