Attention
CSS Bounce Animation
A looping bounce that draws the eye without moving anything else.
Opens with this animation loaded. Nothing is uploaded — the scene travels in the link.
.bounce {
transform: translate3d(208px, 128px, 0);
width: 64px;
height: 64px;
background: #22d3ee;
border-radius: 999px;
animation: bounce-anim 900ms linear 0ms infinite both;
will-change: transform, opacity;
}
@keyframes bounce-anim {
0% {
transform: translate3d(208px, 128px, 0);
animation-timing-function: ease-out;
}
40% {
transform: translate3d(208px, 92px, 0);
animation-timing-function: ease-in;
}
65% {
transform: translate3d(208px, 128px, 0);
animation-timing-function: ease-out;
}
82% {
transform: translate3d(208px, 114px, 0);
animation-timing-function: ease-in;
}
100% {
transform: translate3d(208px, 128px, 0);
}
}
@media (prefers-reduced-motion: reduce) {
.bounce {
animation: none;
transition: none;
}
}Why it is built this way
The squash at the bottom of the bounce is what makes it read as weight rather than a hop. Without it the motion looks like a hovering element rather than one hitting a surface.
What it animates
1 property across 1 CSS declaration. The bar shows when each one is moving.
transformWhat it costs to run
Y is handled by the compositor: no layout, no repaint, and the work can run off the main thread. This is the cheap end of CSS animation, which is why it stays smooth on a slow phone where other properties will not.
It runs for 0.90s across 5 keyframe stops, with every property moving over the same window.
2 curves in play — Ease Out and Ease In on a plain box. Different properties easing differently is how a movement gets texture: the eye reads the mismatch as weight rather than as a mistake.
Accessibility
Nothing here hides content — y 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.