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HTML 

              
                <div class="content">
  <h1 class="title">Some disabilities
    <div class="aurora">
      <div class="aurora__item"></div>
      <div class="aurora__item"></div>
      <div class="aurora__item"></div>
      <div class="aurora__item"></div>
    </div>
  </h1>
  <h1 class="title2">are invisible
    <div class="aurora2">
      <div class="aurora2__item"></div>
      <div class="aurora2__item"></div>
      <div class="aurora2__item"></div>
      <div class="aurora2__item"></div>
    </div>
  </h1>
</div>
!

CSS 

              
                /* Rainbow effect forked from:  https://codepen.io/ostylowany/pen/vYzPVZL */

@import url("https://fonts.googleapis.com/css2?family=Inter:wght@400;800&display=swap");

:root {
  --bg: #000000;
  --clr-1: #00c2ff;
  --clr-2: #33ff8c;
  --clr-3: #ffc640;
  --clr-4: #e54cff;
  --clr-5: #555555;
  --clr-6: #eeeeee;

  --blur: 1rem;
  --fs: clamp(3rem, 8vw, 7rem);
  --ls: clamp(-1.75px, -0.25vw, -3.5px);
}

body {
  min-height: 100vh;
  display: grid;
  place-items: center;
  background-color: var(--bg);
  color: #fff;
  font-family: "Inter", "DM Sans", Arial, sans-serif;
}

*,
*::before,
*::after {
  font-family: inherit;
  box-sizing: border-box;
}

.content {
  text-align: center;
}

.title {
  font-size: var(--fs);
  font-weight: 800;
  letter-spacing: var(--ls);
  position: relative;
  overflow: hidden;
  background: var(--bg);
  margin: 0;
  margin-bottom: -0.5rem;
}

.aurora {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 2;
  mix-blend-mode: darken;
  pointer-events: none;
}

.aurora__item {
  overflow: hidden;
  position: absolute;
  width: 60vw;
  height: 60vw;
  background-color: var(--clr-1);
  border-radius: 37% 29% 27% 27% / 28% 25% 41% 37%;
  filter: blur(var(--blur));
  mix-blend-mode: overlay;
}

.aurora__item:nth-of-type(1) {
  top: -50%;
  animation: aurora-border 12s ease-in-out infinite,
    aurora-1 24s ease-in-out infinite alternate;
}

.aurora__item:nth-of-type(2) {
  background-color: var(--clr-3);
  right: 0;
  top: 0;
  animation: aurora-border 12s ease-in-out infinite,
    aurora-2 24s ease-in-out infinite alternate;
}

.aurora__item:nth-of-type(3) {
  background-color: var(--clr-2);
  left: 0;
  bottom: 0;
  animation: aurora-border 12s ease-in-out infinite,
    aurora-3 16s ease-in-out infinite alternate;
}

.aurora__item:nth-of-type(4) {
  background-color: var(--clr-4);
  right: 0;
  bottom: -50%;
  animation: aurora-border 12s ease-in-out infinite,
    aurora-4 48s ease-in-out infinite alternate;
}

@keyframes aurora-1 {
  0% {
    top: 0;
    right: 0;
  }

  50% {
    top: 100%;
    right: 75%;
  }

  75% {
    top: 100%;
    right: 25%;
  }

  100% {
    top: 0;
    right: 0;
  }
}

@keyframes aurora-2 {
  0% {
    top: -50%;
    left: 0%;
  }

  60% {
    top: 100%;
    left: 75%;
  }

  85% {
    top: 100%;
    left: 25%;
  }

  100% {
    top: -50%;
    left: 0%;
  }
}

@keyframes aurora-3 {
  0% {
    bottom: 0;
    left: 0;
  }

  40% {
    bottom: 100%;
    left: 75%;
  }

  65% {
    bottom: 40%;
    left: 50%;
  }

  100% {
    bottom: 0;
    left: 0;
  }
}

@keyframes aurora-4 {
  0% {
    bottom: -50%;
    right: 0;
  }

  50% {
    bottom: 0%;
    right: 40%;
  }

  90% {
    bottom: 50%;
    right: 25%;
  }

  100% {
    bottom: -50%;
    right: 0;
  }
}

@keyframes aurora-border {
  0% {
    border-radius: 37% 29% 27% 27% / 28% 25% 41% 37%;
  }

  25% {
    border-radius: 47% 29% 39% 49% / 61% 19% 66% 26%;
  }

  50% {
    border-radius: 57% 23% 47% 72% / 63% 17% 66% 33%;
  }

  75% {
    border-radius: 28% 49% 29% 100% / 93% 20% 64% 25%;
  }

  100% {
    border-radius: 37% 29% 27% 27% / 28% 25% 41% 37%;
  }
}

/* Invisible theme */
.title2 {
  font-size: var(--fs);
  font-weight: 800;
  letter-spacing: var(--ls);
  position: relative;
  overflow: hidden;
  background: var(--bg);
  margin: 0;
}

.aurora2 {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 2;
  mix-blend-mode: darken;
  pointer-events: none;
}

.aurora2__item {
  overflow: hidden;
  position: absolute;
  width: 60vw;
  height: 60vw;
  background-color: var(--clr-5);
  border-radius: 37% 29% 27% 27% / 28% 25% 41% 37%;
  filter: blur(var(--blur));
  mix-blend-mode: overlay;
}

.aurora2__item:nth-of-type(1) {
  top: -50%;
  animation: aurora-border 12s ease-in-out infinite,
    aurora-1 24s ease-in-out infinite alternate;
}

.aurora2__item:nth-of-type(2) {
  background-color: var(--clr-5);
  right: 0;
  top: 0;
  animation: aurora-border 12s ease-in-out infinite,
    aurora-2 24s ease-in-out infinite alternate;
}

.aurora2__item:nth-of-type(3) {
  background-color: var(--clr-5);
  left: 0;
  bottom: 0;
  animation: aurora-border 12s ease-in-out infinite,
    aurora-3 16s ease-in-out infinite alternate;
}

.aurora2__item:nth-of-type(4) {
  background-color: var(--clr-5);
  right: 0;
  bottom: -50%;
  animation: aurora-border 12s ease-in-out infinite,
    aurora-4 48s ease-in-out infinite alternate;
}

/* Code for a prefers contrast version of this demo. The default value is no preference.

Current browser support for @prefers-contrast is 92% - https://caniuse.com/mdn-css_at-rules_media_prefers-contrast */

@media (prefers-contrast: more) {
  .title2 {
    color: var(--clr-6);
  }

  .aurora2__item:nth-of-type(1),
  .aurora2__item:nth-of-type(2),
  .aurora2__item:nth-of-type(3),
  .aurora2__item:nth-of-type(4) {
    background-color: var(--clr-6);
  }
}

@media (prefers-contrast: less) {
  .title {
    color: var(--clr-5);
  }

  .aurora__item:nth-of-type(1),
  .aurora__item:nth-of-type(2),
  .aurora__item:nth-of-type(3),
  .aurora__item:nth-of-type(4) {
    background-color: var(--clr-5);
  }
}

@media (prefers-contrast: custom) {
  .aurora2__item:nth-of-type(1) {
    background-color: var(--clr-1);
  }
  .aurora2__item:nth-of-type(2) {
    background-color: var(--clr-2);
  }
  .aurora2__item:nth-of-type(3) {
    background-color: var(--clr-3);
  }
  .aurora2__item:nth-of-type(4) {
    background-color: var(--clr-4);
  }
}

/* Code for a prefers reduced transparency version of this demo. The default value is no preference.

Current browser support for @prefers-reduced-transparency is 0% - https://caniuse.com/mdn-css_at-rules_media_prefers-reduced-transparency */

@media (prefers-reduced-transparency: reduce) {
  .title,
  .title2 {
    opacity: 0.7;
  }
}
!

JS
!
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