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JavaScript

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HTML 

              
                <div></div>

<div></div>

<div></div>
!

CSS 

              
                :root {
  --bounce-easing: linear(
    0, 0.0157, 0.0625, 0.1407, 0.25 18.18%, 0.5625, 1 36.36%, 0.8907, 0.8125,
    0.7657, 0.75, 0.7657, 0.8125, 0.8905, 1, 0.9532, 0.9375, 0.9531, 1, 0.9844, 1
  );
  
    --spring-easing: linear(
    0, 0.009, 0.035 2.1%, 0.141, 0.281 6.7%, 0.723 12.9%, 0.938 16.7%, 1.017,
    1.077, 1.121, 1.149 24.3%, 1.159, 1.163, 1.161, 1.154 29.9%, 1.129 32.8%,
    1.051 39.6%, 1.017 43.1%, 0.991, 0.977 51%, 0.974 53.8%, 0.975 57.1%,
    0.997 69.8%, 1.003 76.9%, 1.004 83.8%, 1
  );
 
  --elastic-easing: linear(
    0, 0.218 2.1%, 0.862 6.5%, 1.114, 1.296 10.7%, 1.346, 1.37 12.9%, 1.373,
    1.364 14.5%, 1.315 16.2%, 1.032 21.8%, 0.941 24%, 0.891 25.9%, 0.877,
    0.869 27.8%, 0.87, 0.882 30.7%, 0.907 32.4%, 0.981 36.4%, 1.012 38.3%, 1.036,
    1.046 42.7% 44.1%, 1.042 45.7%, 0.996 53.3%, 0.988, 0.984 57.5%, 0.985 60.7%,
    1.001 68.1%, 1.006 72.2%, 0.998 86.7%, 1
  );
}

@keyframes reveal {
  from {
    translate: 0 -100px;
    opacity: 0;
    scale: .5;
  }
  to {
    translate: 0 0;
    opacity: 1;
    scale: 1;
  }
}

div {
  background-color: red;
  height: 120px;
  aspect-ratio: 1 / 1;
  opacity: 0;
  animation-name: reveal;
  animation-duration: 1s;
  animation-fill-mode: forwards;
}

div:first-child {
  animation-timing-function: var(--bounce-easing);
}

div:nth-child(2) {
  background-color: green;
   animation-timing-function: var(--spring-easing);
}

div:nth-child(3) {
  background-color: blue;
   animation-timing-function: var(--elastic-easing);
}

body {
  display: flex;
  gap: 42px;
  justify-content: center;
  align-content: center;
  align-items: center;
  height: 100vh;
}
!

JS
!
999px

Console