Grid settle, slow beat

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>Grid settle — slow beat</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: 3.2s;
  --t: calc(var(--cycle) / var(--speed));

  --ease-out: cubic-bezier(0.23, 1, 0.32, 1);
}

* { 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);
}

.panel {
  width: min(400px, 90vw);
  padding: clamp(14px, 4vw, 20px);
  background: var(--paper);
  border: 1px solid var(--oat);
  border-radius: calc(4px * var(--round));
}

.head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  padding-bottom: clamp(9px, 2.6vw, 12px);
  border-bottom: 1px solid var(--oat);
}

.head b {
  font-size: clamp(11.5px, 3.1vw, 13px);
  font-weight: 600;
  letter-spacing: 0.02em;
}

.head span {
  font-size: clamp(11px, 2.9vw, 11.5px);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--clay-d);
}

.rows {
  display: grid;
  gap: clamp(8px, 2.4vw, 11px);
  margin-top: clamp(11px, 3vw, 14px);
}

.row {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 10px;
  animation: settle-loop var(--t) linear infinite both;
}

.label {
  height: 7px;
  background: var(--oat);
  border-radius: 999px;
}

.row:nth-child(1) .label { width: 62%; }
.row:nth-child(2) .label { width: 44%; }
.row:nth-child(3) .label { width: 71%; }
.row:nth-child(4) .label { width: 52%; }

.dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--oat);
}

.row:nth-child(2) .dot { background: var(--clay); }
.row:nth-child(4) .dot { background: var(--olive); }

.meter {
  margin-top: clamp(13px, 3.4vw, 17px);
  height: 6px;
  background: var(--oat);
  border-radius: 999px;
  overflow: hidden;
}

.meter i {
  display: block;
  height: 100%;
  background: var(--clay);
  border-radius: 999px;
  animation: wipe var(--t) linear infinite both;
}

.foot {
  margin-top: clamp(9px, 2.6vw, 11px);
  font-size: clamp(11px, 2.9vw, 11.5px);
  letter-spacing: 0.06em;
  color: var(--slate);
  opacity: 0.55;
}

/* 400ms move inside the 3.2s loop = 12.5%. The eased sub-curve is written
   into the keyframe stops so the ease-out shape survives the linear carrier. */
@keyframes settle-loop {
  0%     { transform: translateY(7px); opacity: 0.35; animation-timing-function: var(--ease-out); }
  12.5%  { transform: translateY(0);   opacity: 1; }
  100%   { transform: translateY(0);   opacity: 1; }
}

@keyframes wipe {
  0%     { clip-path: inset(0 100% 0 0); animation-timing-function: var(--ease-out); }
  12.5%  { clip-path: inset(0 32% 0 0); }
  100%   { clip-path: inset(0 32% 0 0); }
}

@media (max-width: 380px) {
  .panel { padding: 13px; }
}

@media (prefers-reduced-motion: reduce) {
  .row {
    animation-name: settle-fade;
    animation-duration: calc(var(--cycle) * 2 / var(--speed));
  }
  .meter i {
    animation-name: hold-fade;
    animation-duration: calc(var(--cycle) * 2 / var(--speed));
    clip-path: inset(0 32% 0 0);
  }
  @keyframes settle-fade {
    0%   { transform: none; opacity: 0.5; }
    12%  { transform: none; opacity: 1; }
    100% { transform: none; opacity: 1; }
  }
  @keyframes hold-fade {
    0%   { opacity: 0.5; }
    12%  { opacity: 1; }
    100% { opacity: 1; }
  }
}
</style>
</head>
<body>
  <div class="panel">
    <div class="head">
      <b>Output settings</b>
      <span>Applied</span>
    </div>
    <div class="rows">
      <div class="row"><div class="label"></div><div class="dot"></div></div>
      <div class="row"><div class="label"></div><div class="dot"></div></div>
      <div class="row"><div class="label"></div><div class="dot"></div></div>
      <div class="row"><div class="label"></div><div class="dot"></div></div>
    </div>
    <div class="meter"><i></i></div>
    <div class="foot">Recalculated from 4 inputs</div>
  </div>
</body>
</html>

The variant family

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