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CSS

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CSS Base

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JavaScript

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HTML 

              
                <div class="pulsing-1"></div>
<div class="pulsing-2"></div>
<div class="pulsing-3"></div>
<div class="pulsing-4"></div>
<div class="pulsing-5"></div>
<div class="pulsing-6"></div>
<div class="pulsing-7"></div>
<div class="pulsing-8"></div>
<div class="pulsing-9"></div>
<div class="pulsing-10" data-c="💯"></div>
!

CSS 

              
                .pulsing-1 {
  width:20px;
  height:20px;
  border-radius: 50%;
  background:#000;
  box-shadow: 0 0 0 0 #0004;
  animation:pl1 1s infinite;
}
@keyframes pl1 {
    100% {box-shadow: 0 0 0 30px #0000}
}

.pulsing-2 {
  width:20px;
  height:20px;
  border-radius: 50%;
  background:#000;
  box-shadow: 0 0 0 0 #0004;
  animation:pl2 1.5s infinite linear;
  position: relative;
}
.pulsing-2:before,
.pulsing-2:after {
  content:"";
  position: absolute;
  inset:0;
  border-radius: inherit;
  box-shadow: 0 0 0 0 #0004;
  animation: inherit;
  animation-delay: -0.5s;
}
.pulsing-2:after {
  animation-delay: -1s;
}
@keyframes pl2 {
    100% {box-shadow: 0 0 0 40px #0000}
}

.pulsing-3 {
  width:50px;
  height:50px;
  color:#dc1818;
  background:
   radial-gradient(circle at 60% 65%, currentColor 62%, #0000 65%) top left,
   radial-gradient(circle at 40% 65%, currentColor 62%, #0000 65%) top right,
   linear-gradient(to bottom left, currentColor 42%,#0000 43%) bottom left ,
   linear-gradient(to bottom right,currentColor 42%,#0000 43%) bottom right;
  background-size:50% 50%;
  background-repeat:no-repeat;
  position:relative;
}
.pulsing-3:after {
  content:"";
  position:absolute;
  inset:0;
  background:inherit;
  opacity:0.4;
  animation:pl3 1s infinite;
}
@keyframes pl3 {
  to {transform:scale(1.8);opacity:0}
}

.pulsing-4 {
  width:60px;
  height:60px;
  position:relative;
}
.pulsing-4:before,
.pulsing-4:after {
  content:"";
  position:absolute;
  border-radius: 50%;
  inset:0;
  background:
    radial-gradient(circle 10px,#f85c00 94%,#0000),
    repeating-conic-gradient(from -30deg,#0000 0 60deg,#f85c00 61deg 120deg);
  -webkit-mask:radial-gradient(circle 15px,#000 calc(100% - 6px),#0000 calc(100% - 5px) 94%,#000);
}

.pulsing-4:after {
  animation:pl4 1s infinite;
  transform: perspective(300px) translateZ(0px)
}

@keyframes pl4 {
  to {transform:perspective(300px) translateZ(150px);opacity:0}
}



.pulsing-5 {
  width:80px;
  height:80px;
  position:relative;
}
.pulsing-5:before,
.pulsing-5:after {
  content:"";
  position:absolute;
  inset:0;
  background:#ffb940;    
  box-shadow: 0 0 0 50px;
  clip-path: polygon(50% 0%, 61% 35%, 98% 35%, 68% 57%, 79% 91%, 50% 70%, 21% 91%, 32% 57%, 2% 35%, 39% 35%);
}

.pulsing-5:after {
  animation:pl5 1s infinite;
  transform:perspective(300px) translateZ(0px)
}

@keyframes pl5 {
  to {transform:perspective(300px) translateZ(150px);opacity:0}
}

.pulsing-6 {
  width:40px;
  height:40px;
  position:relative;
  transform:rotate(45deg);
}
.pulsing-6:before,
.pulsing-6:after {
  content:"";
  position:absolute;
  inset:0;
  border-radius: 50% 50% 0 50%;
  background:#514b82;
  -webkit-mask:radial-gradient(circle 10px at 50% 50%,#0000 94%,#000);
}

.pulsing-6:after {
  animation:pl6 1s infinite;
  transform: perspective(300px) translateZ(0px)
}

@keyframes pl6 {
  to {transform:perspective(300px) translateZ(150px);opacity:0}
}

.pulsing-7 {
  width: 108px;
  height: 60px;
  color:#269af2;
  --c:radial-gradient(farthest-side,currentColor 96%,#0000);
  background: 
    var(--c) 100% 100% /30% 60%,
    var(--c) 70%  0    /50% 100%,
    var(--c) 0    100% /36% 68%,
    var(--c) 27%  18%  /26% 40%,
    linear-gradient(currentColor 0 0) bottom/67% 58%;
  background-repeat: no-repeat;
  position: relative;
}

.pulsing-7:after {
  content:"";
  position:absolute;
  inset:0;
  background:inherit;
  opacity:0.4;
  animation:pl7 1s infinite;
}
@keyframes pl7 {
  to {transform:scale(1.8);opacity:0}
}

.pulsing-8 {
  width:65px;
  height:117px;
  position:relative;
}
.pulsing-8:before,
.pulsing-8:after {
  content:"";
  position:absolute;
  inset:0;
  background:#ff8001;    
  box-shadow: 0 0 0 50px;
  clip-path: polygon(100% 0, 23% 46%, 46% 44%, 15% 69%, 38% 67%, 0 100%, 76% 57%, 53% 58%, 88% 33%, 60% 37%);;
}

.pulsing-8:after {
  animation:pl8 1s infinite;
  transform:perspective(300px) translateZ(0px)
}

@keyframes pl8 {
  to {transform:perspective(300px) translateZ(180px);opacity:0}
}
.pulsing-9 {
  width:100px;
  height:45px;
  position:relative;
}
.pulsing-9:before,
.pulsing-9:after {
  content:"";
  position:absolute;
  inset:0;
  background:#000;    
  box-shadow: 0 0 0 50px;
  clip-path: polygon(-50px -20px,10% -12px,20% 0,calc(50% - 15px) 0,calc(50% - 10px) -20px,calc(50% - 8px) -15px,calc(50% + 8px) -15px,calc(50% + 10px) -20px,calc(50% + 15px) 0,80% 0,90% -12px,calc(100% + 50px) -20px,100% 80%,calc(100% + 10px) calc(100% + 10px),60% 100%,50% calc(100% + 15px),40% 100%,-10px calc(100% + 10px),0 80%);
}

.pulsing-9:after {
  animation:pl9 1s infinite;
  transform:perspective(300px) translateZ(0px)
}

@keyframes pl9 {
  to {transform:perspective(300px) translateZ(100px);opacity:0}
}

.pulsing-10 {
  display: grid;
  font-size: 50px;
}
.pulsing-10:before,
.pulsing-10:after {
  content:attr(data-c);
  grid-area: 1/1;
}

.pulsing-10:after {
  animation:pl10 1s infinite;
}

@keyframes pl10 {
  to {transform:scale(1.8);opacity:0}
}

/**/
body {
  display: grid;
  grid-template-columns: repeat(auto-fit,minmax(250px,1fr));
  grid-auto-rows: 130px;
  place-items:center;
}

* {
  box-sizing: border-box;
}
!

JS
!
999px

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