R to re-roll · Esc to reset

Bleed fill confirm

Variant: Ease-out

A save button whose confirmation state floods in from the press point as a circular clip-path wipe, then a check stroke draws and the label swaps. Reach for it when a primary action commits and you want the button itself to carry the receipt instead of a toast. The fill uses a strong ease-out so the flood covers most of its distance in the first third of the 260ms wipe — the eye is on the button at press, so the information arrives immediately and the tail is just settling.

buttonconfirmationclip-pathfeedbackstate-change

The source

A complete HTML document. Paste it into an empty .html file and it plays — no stylesheet, script, font, or image to fetch.

<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<title>Bleed fill confirm — ease-out</title>
<style>
:root {
  /* Neutrals — fixed, never remixed. */
  --ivory: #faf9f5;
  --paper: #ffffff;
  --oat: #e3dacc;
  --slate: #141413;

  /* Knobs — the remix API. A knob exists iff declared here and used below. */
  --hue: 38.8;
  --lift: 0;
  --chroma: 1;
  --round: 1;
  --speed: 1;

  /* Accents — derived from the knobs with the family's offsets baked in,
     so one hue roll moves them together. Defaults reproduce the original hex
     (#d97757 / #b85c3e / #788c5d / #b04a3f). */
  --clay: oklch(calc(0.6724 + var(--lift)) calc(0.1308 * var(--chroma)) var(--hue));
  --clay-d: oklch(calc(0.5797 + var(--lift)) calc(0.127 * var(--chroma)) var(--hue));
  --olive: oklch(calc(0.6118 + var(--lift)) calc(0.0713 * var(--chroma)) calc(var(--hue) + 88.3));
  --rust: oklch(calc(0.5408 + var(--lift)) calc(0.1357 * var(--chroma)) calc(var(--hue) - 10.3));

  /* Clock — every duration in the document runs off --t. */
  --cycle: 3.6s;
  --t: calc(var(--cycle) / var(--speed));

  --ease-out: cubic-bezier(0.23, 1, 0.32, 1);
  --ease-accent: cubic-bezier(0.23, 1, 0.32, 1); /* the fill curve — the axis of this family */

  /* file-specific sub-clocks, all divided by the same --speed */
  --_press: calc(140ms / var(--speed));
  --_wipe: calc(260ms / var(--speed));
  --_check: calc(240ms / var(--speed));
}

* { box-sizing: border-box; }

html, body { margin: 0; }

body {
  min-height: 100vh;
  display: grid;
  place-items: center;
  background: var(--ivory);
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  color: var(--slate);
  -webkit-font-smoothing: antialiased;
}

.stage {
  width: min(340px, 88vw);
  display: grid;
  justify-items: center;
  gap: clamp(14px, 4vw, 20px);
  padding: clamp(12px, 4vw, 20px);
}

.rule {
  width: 100%;
  height: 1px;
  background: var(--oat);
}

.btn {
  position: relative;
  isolation: isolate;
  width: min(230px, 76vw);
  height: clamp(46px, 13vw, 52px);
  border-radius: calc(10px * var(--round));
  background: var(--paper);
  border: 1px solid var(--oat);
  overflow: hidden;
  display: grid;
  place-items: center;
  transform-origin: 50% 50%;
  animation: press var(--t) var(--ease-out) infinite;
}

/* The flood: a circle clip growing from the press point, not from centre. */
.fill {
  position: absolute;
  inset: 0;
  background: var(--clay-d);
  clip-path: circle(0% at 26% 62%);
  animation: flood var(--t) var(--ease-accent) infinite;
}

/* A hairline of the lighter accent rides just ahead of the flood edge,
   so the boundary reads as absorbed rather than as a hard mask. */
.halo {
  position: absolute;
  inset: 0;
  background: var(--clay);
  clip-path: circle(0% at 26% 62%);
  animation: halo var(--t) var(--ease-accent) infinite;
}

.label {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: clamp(13px, 3.6vw, 14px);
  font-weight: 560;
  letter-spacing: 0.01em;
}

.word {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  white-space: nowrap;
}

.word.a {
  color: var(--slate);
  animation: wordOut var(--t) var(--ease-out) infinite;
}

.word.b {
  color: var(--paper);
  padding-left: 24px;
  opacity: 0;
  animation: wordIn var(--t) var(--ease-out) infinite;
}

.tick {
  position: absolute;
  left: 50%;
  z-index: 2;
  width: 16px;
  height: 16px;
  margin-left: -58px;
  opacity: 0;
  animation: tickShow var(--t) var(--ease-out) infinite;
}

.tick path {
  fill: none;
  stroke: var(--paper);
  stroke-width: 2.2;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-dasharray: 22;
  stroke-dashoffset: 22;
  animation: draw var(--t) var(--ease-out) infinite;
}

.caption {
  font-size: clamp(10.5px, 2.9vw, 11.5px);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--slate);
  opacity: 0.45;
}

/* 0–4% press, 4–11% flood, then hold, then reset in the last slice. */
@keyframes press {
  0%, 2%   { transform: scale(1); }
  4.5%     { transform: scale(0.978); }
  11%      { transform: scale(1); }
  100%     { transform: scale(1); }
}

@keyframes flood {
  0%, 4%   { clip-path: circle(0% at 26% 62%); }
  11.5%    { clip-path: circle(130% at 26% 62%); }
  88%      { clip-path: circle(130% at 26% 62%); }
  96%, 100% { clip-path: circle(0% at 26% 62%); }
}

@keyframes halo {
  0%, 3.4% { clip-path: circle(0% at 26% 62%); }
  10.4%    { clip-path: circle(130% at 26% 62%); }
  88%      { clip-path: circle(130% at 26% 62%); }
  95.4%, 100% { clip-path: circle(0% at 26% 62%); }
}

@keyframes wordOut {
  0%, 3%   { opacity: 1; transform: translateX(-50%) translateY(0); }
  8%       { opacity: 0; transform: translateX(-50%) translateY(-6px); }
  90%      { opacity: 0; transform: translateX(-50%) translateY(-6px); }
  97%, 100% { opacity: 1; transform: translateX(-50%) translateY(0); }
}

@keyframes wordIn {
  0%, 7%   { opacity: 0; transform: translateX(-50%) translateY(6px); }
  14%      { opacity: 1; transform: translateX(-50%) translateY(0); }
  88%      { opacity: 1; transform: translateX(-50%) translateY(0); }
  93%, 100% { opacity: 0; transform: translateX(-50%) translateY(6px); }
}

@keyframes tickShow {
  0%, 9%   { opacity: 0; }
  13%      { opacity: 1; }
  88%      { opacity: 1; }
  92%, 100% { opacity: 0; }
}

@keyframes draw {
  0%, 10%  { stroke-dashoffset: 22; }
  20%      { stroke-dashoffset: 0; }
  88%      { stroke-dashoffset: 0; }
  92%, 100% { stroke-dashoffset: 22; }
}

@media (max-width: 380px) {
  .stage { gap: 12px; padding: 10px; }
}

@media (prefers-reduced-motion: reduce) {
  /* Keep the meaning — colour and label still change — drop the wipe and travel.
     Cycle stretched ~1.9x so the state swap is a slow cross-fade, not a blink. */
  :root { --t: calc(6.8s / var(--speed)); }

  .btn { animation: none; }

  .fill {
    clip-path: circle(130% at 26% 62%);
    animation: fadeFill var(--t) ease infinite;
  }
  .halo { display: none; }

  .word.a { animation: softOut var(--t) ease infinite; }
  .word.b { animation: softIn var(--t) ease infinite; }
  .tick { animation: tickShow var(--t) ease infinite; }
  .tick path { stroke-dashoffset: 0; animation: none; }

  @keyframes fadeFill {
    0%, 8%   { opacity: 0; }
    22%, 88% { opacity: 1; }
    98%, 100% { opacity: 0; }
  }
  @keyframes softOut {
    0%, 6%   { opacity: 1; transform: translateX(-50%); }
    20%, 90% { opacity: 0; transform: translateX(-50%); }
    100%     { opacity: 1; transform: translateX(-50%); }
  }
  @keyframes softIn {
    0%, 10%  { opacity: 0; transform: translateX(-50%); }
    24%, 88% { opacity: 1; transform: translateX(-50%); }
    98%, 100% { opacity: 0; transform: translateX(-50%); }
  }
}
</style>
</head>
<body>
  <div class="stage">
    <div class="rule"></div>
    <div class="btn">
      <div class="fill"></div>
      <div class="halo"></div>
      <svg class="tick" viewBox="0 0 16 16" aria-hidden="true">
        <path d="M3 8.4 L6.4 11.8 L13 4.6" />
      </svg>
      <div class="label">
        <span class="word a">Save changes</span>
        <span class="word b">Saved</span>
      </div>
    </div>
    <div class="caption">Commit state</div>
    <div class="rule"></div>
  </div>
</body>
</html>

The variant family

Same idea, one axis moved. Compare them side by side before you commit.