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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.

              <div class="one"></div>
              $num: 1000; // Number of particles (<2000) Gif is 1900
$sat: 90; // Color saturation
$light: 60; // Color lightness
$dur: 3.5s; // Animation duration

/* Shape at start of animation */
// Play with these options...
$startOptions: (
  size: 3px,
  width: 30,
  height: 30,
  loops: 3,
  twists: 1,

  minHue: 0,
  maxHue: 360

/* Shape at end of animation */
// ... and these options
$endOptions: (
  size: 3px,
  width: 0.125,
  height: 0.125,
  loops: 12,
  twists: 16,
  minHue: 0,
  maxHue: 360

/* Shortcut functions to call options from maps above */
@function s($option){
  @return map-get($startOptions,$option);

@function e($option){
  @return map-get($endOptions,$option);

/* Set color based on min/max hue and current shadow */
@function hueRange($shadow, $hue) {
  $minHue: call($shadow, minHue);
  $maxHue: call($shadow, maxHue);
	@return $hue / $num * ($maxHue - $minHue) + $minHue;

/* Lists to hold shadows */
$start-shadow: ();
$end-shadow: ();

// Build box-shadow lists
@for $n from 0 through $num {
  $start-shadow: append($start-shadow, 
    sin($n  // position x
      * s(loops)) 
      * s(size) 
      * s(width)
    cos($n  // position y
      * s(twists)) 
      * s(size) 
      * s(height)
    0 // blur
    hsl(hueRange(s,$n),$sat,$light) // color 
    , comma); 

  // End shadow, same structure as above but with cos/sine reversed
  $end-shadow: append($end-shadow, cos($n * e(loops)) * e(size) * $n * e(width)
    sin($n * e(twists)) * e(size) * $n * e(height) 0 hsl(hueRange(e,$n),$sat,$light), comma);

// Body styling
body {
  background: hsl(230,70,10);

.one {
  // Div styling
  background: transparent;
  width: s(size);
  height: s(size);
  border-radius: 50%;
  // Center div
  position: absolute;
    top: 50%;
    left: 50%;
  margin-top: s(size);
  margin-left: s(size);
  // Magic
  animation: anim $dur infinite alternate ease-in-out;
  box-shadow: $start-shadow;

@keyframes anim {
  5% {
    box-shadow: $start-shadow;
  95%,100% {
    box-shadow: $end-shadow;
    width: e(size);
    height: e(size);
              // v1: https://codepen.io/giana/pen/JGdbje/
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