Modern CSS Filter Effects
Grayscale, blur, hue, sepia, duotone and glow filters for photos, logos, icons and text.
1Neon Glow
Wraps icons, logos and transparent images in a flickering neon halo using drop-shadow. Class: fx-filter-neon-glow
<div class="d-flex flex-wrap align-items-center justify-content-center gap-3 p-3 h-100" style="min-height:200px">
<div class="bg-dark rounded-4 p-4 d-flex gap-4 fs-1">
<span class="fx-filter-neon-glow"><i class="bi bi-lightning-charge-fill" aria-hidden="true"></i></span><span class="fx-filter-neon-glow"><i class="bi bi-music-note-beamed" aria-hidden="true"></i></span><span class="fx-filter-neon-glow"><i class="bi bi-moon-stars-fill" aria-hidden="true"></i></span>
</div>
</div>
/* CSS (already in assets/css/effects.css) */
.fx-filter-neon-glow {
color: var(--wt-primary-ink);
filter: drop-shadow(0 0 4px var(--wt-primary)) drop-shadow(0 0 12px var(--wt-primary));
animation: fx-filter-neon-glow-flicker 3s linear infinite;
}
@keyframes fx-filter-neon-glow-flicker {
0%, 18%, 22%, 62%, 64%, 100% { filter: drop-shadow(0 0 4px var(--wt-primary)) drop-shadow(0 0 12px var(--wt-primary)); }
20%, 63% { filter: drop-shadow(0 0 1px var(--wt-primary)); }
}
@media (prefers-reduced-motion: reduce) {
.fx-filter-neon-glow, .fx-filter-neon-glow::before, .fx-filter-neon-glow::after, .fx-filter-neon-glow *, .fx-filter-neon-glow *::before, .fx-filter-neon-glow *::after { animation: none !important; transition: none !important; }
}2Duotone Effect
Turns any photo into a two-colour print in the theme colours; put the class on a wrapper around the img. Class: fx-duotone-effect
<div class="d-flex flex-wrap align-items-center justify-content-center gap-3 p-3 h-100" style="min-height:200px">
<figure class="fx-duotone-effect rounded-3 mb-0">
<img src="https://images.unsplash.com/photo-1758518731706-be5d5230e5a5?auto=format&fit=crop&w=1200&h=800&q=70" alt="Duotone photo" class="object-fit-cover" style="width:210px;height:145px">
</figure>
</div>
/* CSS (already in assets/css/effects.css) */
.fx-duotone-effect { position: relative; display: inline-block; overflow: hidden; isolation: isolate; background: var(--wt-accent); }
.fx-duotone-effect img { display: block; filter: grayscale(1) contrast(1.2) brightness(1.1); mix-blend-mode: multiply; transition: filter .5s; }
.fx-duotone-effect::after {
content: ""; position: absolute; inset: 0; pointer-events: none;
background: var(--wt-primary); mix-blend-mode: lighten; transition: opacity .5s;
}
.fx-duotone-effect:hover::after { opacity: 0; }
.fx-duotone-effect:hover img { filter: grayscale(0); mix-blend-mode: normal; }
@media (prefers-reduced-motion: reduce) {
.fx-duotone-effect, .fx-duotone-effect::before, .fx-duotone-effect::after, .fx-duotone-effect *, .fx-duotone-effect *::before, .fx-duotone-effect *::after { animation: none !important; transition: none !important; }
}