Modern CSS Transitions
Polished hover and focus transitions for buttons, cards and links that work on any .btn or .card.
1Neon Fill Button
An outline button that fills with colour from the left and glows; works on any .btn or link. Class: fx-neon-fill-button
<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 fx-neon-fill-button">Join now</button>
<a href="#" class="btn fx-neon-fill-button rounded-pill">Learn more <i class="bi bi-arrow-right" aria-hidden="true"></i></a>
</div>
/* CSS (already in assets/css/effects.css) */
.fx-neon-fill-button, .btn.fx-neon-fill-button {
position: relative; isolation: isolate; overflow: hidden; z-index: 0;
color: var(--wt-primary-ink); background: transparent; border: 2px solid var(--wt-primary);
transition: color .35s ease, box-shadow .35s ease;
}
.fx-neon-fill-button::before {
content: ""; position: absolute; inset: 0; z-index: -1; background: var(--wt-primary);
transform: scaleX(0); transform-origin: left center; transition: transform .4s cubic-bezier(.7, 0, .3, 1);
}
.fx-neon-fill-button:hover, .fx-neon-fill-button:focus-visible, .btn.fx-neon-fill-button:hover, .btn.fx-neon-fill-button:focus-visible {
color: var(--wt-on-primary, #fff); border-color: var(--wt-primary);
box-shadow: 0 0 12px rgba(var(--wt-primary-rgb), .6), 0 0 32px rgba(var(--wt-primary-rgb), .35);
}
.fx-neon-fill-button:hover::before, .fx-neon-fill-button:focus-visible::before { transform: scaleX(1); }
@media (prefers-reduced-motion: reduce) {
.fx-neon-fill-button, .fx-neon-fill-button::before, .fx-neon-fill-button::after, .fx-neon-fill-button *, .fx-neon-fill-button *::before, .fx-neon-fill-button *::after { animation: none !important; transition: none !important; }
}2Liquid 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">Dive in</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-ink); 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; }
}