Modern CSS Transitions

Polished hover and focus transitions for buttons, cards and links that work on any .btn or .card.

1Liquid Ripple

A button that fills with a swirling liquid from the bottom on hover. Class: fx-liquid-ripple

<div class="d-flex flex-wrap align-items-center justify-content-center gap-3 p-3 h-100" style="min-height:200px">
  <button type="button" class="btn btn-lg px-4 fx-liquid-ripple">Order now</button>
  <button type="button" class="btn rounded-pill fx-liquid-ripple">Hover me</button>
</div>

/* CSS (already in assets/css/effects.css) */
.fx-liquid-ripple, .btn.fx-liquid-ripple {
  position: relative; isolation: isolate; overflow: hidden; z-index: 0;
  color: var(--wt-primary); background: var(--wt-surface, #fff); border: 2px solid var(--wt-primary);
  transition: color .5s ease;
}
.fx-liquid-ripple::before {
  content: ""; position: absolute; z-index: -1; left: 50%; top: 100%; width: 240%; aspect-ratio: 1;
  margin-left: -120%; margin-top: 12%; border-radius: 42%;
  background: var(--wt-primary);
  transition: top .8s ease, margin-top .8s ease;
  animation: fx-liquid-ripple-swirl 5s linear infinite;
}
.fx-liquid-ripple:hover, .fx-liquid-ripple:focus-visible, .btn.fx-liquid-ripple:hover, .btn.fx-liquid-ripple:focus-visible { color: var(--wt-on-primary, #fff); border-color: var(--wt-primary); }
.fx-liquid-ripple:hover::before, .fx-liquid-ripple:focus-visible::before { top: 50%; margin-top: -120%; }
.fx-liquid-ripple:active { transform: scale(.97); }
@keyframes fx-liquid-ripple-swirl { to { transform: rotate(360deg); } }
@media (prefers-reduced-motion: reduce) {
  .fx-liquid-ripple, .fx-liquid-ripple::before, .fx-liquid-ripple::after, .fx-liquid-ripple *, .fx-liquid-ripple *::before, .fx-liquid-ripple *::after { animation: none !important; transition: none !important; }
}

2Rainbow Glow

Surrounds a button or card with a glow that cycles through the theme colours while hovered. Class: fx-rainbow-glow

Pro plan

<div class="d-flex flex-wrap align-items-center justify-content-center gap-3 p-3 h-100" style="min-height:200px">
  <button type="button" class="btn btn-dark btn-lg rounded-pill fx-rainbow-glow">Go premium</button>
  <div class="card fx-rainbow-glow" style="width:9rem" tabindex="0">
    <div class="card-body text-center py-3">
      <div class="fs-3 text-primary">
        <i class="bi bi-gem" aria-hidden="true"></i>
      </div>
      <div class="small fw-semibold">
        Pro plan
      </div>
    </div>
  </div>
</div>

/* CSS (already in assets/css/effects.css) */
.fx-rainbow-glow { transition: box-shadow .4s ease, transform .4s ease; }
.fx-rainbow-glow:hover, .fx-rainbow-glow:focus-visible { transform: translateY(-2px); animation: fx-rainbow-glow-glow 2.4s linear infinite; }
@keyframes fx-rainbow-glow-glow {
  0%, 100% { box-shadow: 0 0 14px rgba(var(--wt-primary-rgb), .75), 0 0 34px rgba(var(--wt-primary-rgb), .35); }
  33% { box-shadow: 0 0 14px rgba(var(--wt-accent-rgb), .75), 0 0 34px rgba(var(--wt-accent-rgb), .35); }
  66% { box-shadow: 0 0 14px rgba(var(--wt-secondary-rgb), .75), 0 0 34px rgba(var(--wt-secondary-rgb), .35); }
}
@media (prefers-reduced-motion: reduce) {
  .fx-rainbow-glow, .fx-rainbow-glow::before, .fx-rainbow-glow::after, .fx-rainbow-glow *, .fx-rainbow-glow *::before, .fx-rainbow-glow *::after { animation: none !important; transition: none !important; }
}