Advanced Animated Backgrounds

<section class="fx-bg-glitch bg-dark text-white rounded-4 p-4 text-center d-flex flex-column justify-content-center" style="min-height:210px">
  <p class="small text-uppercase fw-semibold mb-1 text-white-50">Glitch</p>
  <h3 class="h4 fw-bold mb-2">Everyday essentials, beautifully made</h3>
  <p class="small mb-3 text-white-50">Content stays readable on top of the moving background.</p>
  <div>
    <a href="#" class="btn btn-primary btn-sm">Get started</a>
  </div>
</section>

/* CSS (already in assets/css/effects.css) */
.fx-bg-glitch { position: relative; isolation: isolate; overflow: hidden; }
.fx-bg-glitch::before, .fx-bg-glitch::after { content: ""; position: absolute; pointer-events: none; z-index: -1; }
.fx-bg-glitch::before {
  inset: 0;
  background: repeating-linear-gradient(0deg, rgba(var(--wt-primary-rgb), .07) 0 2px, transparent 2px 5px);
}
.fx-bg-glitch::after {
  inset: 0;
  background: linear-gradient(90deg, rgba(var(--wt-accent-rgb), .22), rgba(var(--wt-primary-rgb), .22) 50%, rgba(var(--wt-secondary-rgb), .22));
  -webkit-clip-path: inset(50% 0 50% 0); clip-path: inset(50% 0 50% 0);
  animation: fx-bg-glitch-bands 4s steps(1) infinite;
}
@keyframes fx-bg-glitch-bands {
  0%, 70%, 100% { -webkit-clip-path: inset(50% 0 50% 0); clip-path: inset(50% 0 50% 0); transform: none; }
  72% { -webkit-clip-path: inset(12% 0 78% 0); clip-path: inset(12% 0 78% 0); transform: translateX(-3%); }
  75% { -webkit-clip-path: inset(58% 0 30% 0); clip-path: inset(58% 0 30% 0); transform: translateX(4%); }
  78% { -webkit-clip-path: inset(30% 0 62% 0); clip-path: inset(30% 0 62% 0); transform: translateX(-2%); }
  81% { -webkit-clip-path: inset(80% 0 6% 0); clip-path: inset(80% 0 6% 0); transform: translateX(3%); }
  84% { -webkit-clip-path: inset(50% 0 50% 0); clip-path: inset(50% 0 50% 0); }
}
@media (prefers-reduced-motion: reduce) {
  .fx-bg-glitch, .fx-bg-glitch::before, .fx-bg-glitch::after, .fx-bg-glitch *, .fx-bg-glitch *::before, .fx-bg-glitch *::after { animation: none !important; transition: none !important; }
}

<section class="fx-bg-parallax bg-body border rounded-4 p-4 text-center d-flex flex-column justify-content-center" style="min-height:210px">
  <p class="small text-uppercase fw-semibold mb-1 text-body-secondary">Parallax depth</p>
  <h3 class="h4 fw-bold mb-2">New season, new favourites</h3>
  <p class="small mb-3 text-body-secondary">Content stays readable on top of the moving background.</p>
  <div>
    <a href="#" class="btn btn-primary btn-sm">Get started</a>
  </div>
</section>

/* CSS (already in assets/css/effects.css) */
.fx-bg-parallax { position: relative; isolation: isolate; overflow: hidden; }
.fx-bg-parallax::before, .fx-bg-parallax::after { content: ""; position: absolute; pointer-events: none; z-index: -1; }
.fx-bg-parallax::before {
  inset: 0;
  background-image:
    radial-gradient(circle, rgba(var(--wt-primary-rgb), .35) 0 1px, transparent 1.5px),
    radial-gradient(circle, rgba(var(--wt-secondary-rgb), .4) 0 2px, transparent 2.5px);
  background-size: 24px 24px, 70px 70px;
  animation: fx-bg-parallax-layers 20s linear infinite;
}
.fx-bg-parallax::after {
  inset: 0;
  background-image:
    radial-gradient(circle, rgba(var(--wt-accent-rgb), .22) 0 18px, transparent 32px),
    radial-gradient(circle, rgba(var(--wt-primary-rgb), .18) 0 26px, transparent 44px);
  background-size: 220px 220px, 340px 340px;
  background-position: 30px 60px, 180px 10px;
  animation: fx-bg-parallax-near 20s linear infinite;
}
@keyframes fx-bg-parallax-layers { to { background-position: -24px 0, -140px 0; } }
@keyframes fx-bg-parallax-near { to { background-position: -410px 60px, -500px 10px; } }
@media (prefers-reduced-motion: reduce) {
  .fx-bg-parallax, .fx-bg-parallax::before, .fx-bg-parallax::after, .fx-bg-parallax *, .fx-bg-parallax *::before, .fx-bg-parallax *::after { animation: none !important; transition: none !important; }
}