Reveals
Iris In Reveal
Opens from the centre outward in a circle.
Opens with this animation loaded. Nothing is uploaded — the scene travels in the link.
.iris-in {
transform: translate3d(180px, 100px, 0);
-webkit-mask-image: radial-gradient(circle at 50% 50%, #000 90%, transparent 100%);
mask-image: radial-gradient(circle at 50% 50%, #000 90%, transparent 100%);
width: 120px;
height: 120px;
background: #6366f1;
border-radius: 20px;
animation: iris-in-anim 900ms linear 0ms infinite both;
will-change: transform, opacity;
}
@keyframes iris-in-anim {
0% {
-webkit-mask-image: radial-gradient(circle at 50% 50%, #000 0%, transparent 0%);
mask-image: radial-gradient(circle at 50% 50%, #000 0%, transparent 0%);
animation-timing-function: ease-out;
}
100% {
-webkit-mask-image: radial-gradient(circle at 50% 50%, #000 90%, transparent 100%);
mask-image: radial-gradient(circle at 50% 50%, #000 90%, transparent 100%);
}
}
@media (prefers-reduced-motion: reduce) {
.iris-in {
animation: none;
transition: none;
}
}Why it is built this way
A radial mask growing from the middle. The classic film transition, and worth reserving for something that deserves the drama — it draws far more attention than a wipe.
What it animates
1 property across 1 CSS declaration. The bar shows when each one is moving.
mask-imageWhat it costs to run
Mask-image repaints on every frame rather than running on the compositor. There is no reflow, so this is far cheaper than animating width or height — but keep the painted area modest.
It runs for 0.90s across 2 keyframe stops, with every property moving over the same window.
One curve throughout: Ease Out on a plain box. Keeping a single easing across every property is what makes a multi-property animation read as one movement rather than several things happening at once.
Accessibility
Nothing here hides content — mask-image moves over 0.90s and the element is visible throughout. The exported prefers-reduced-motion guard still silences it, which matters most for the looping ones: motion that never stops is the kind that makes people feel unwell.