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Detent dial select, motor-driven
Variant: Motor (linear)
The same selector knob turned at a constant rate, as if a small servo drives it instead of a hand. Use it when the system makes the change itself, such as a setting synced from another device or an automatic mode step, and you want the motion to look mechanical rather than human. Linear is the honest curve for a motor, and it only works here because the turn is short (about 288ms) and stops hard at the click position.
dialstate-changerotationmechanicalautomatic
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>Detent dial select — motor</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; /* include ONLY if at least one border-radius is wrapped below */
--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; /* the authored master loop */
--t: calc(var(--cycle) / var(--speed));
--_s: min(210px, 72vmin);
--_loop: var(--t);
--_shade: color-mix(in oklab, var(--slate) 22%, transparent);
--_shade-soft: color-mix(in oklab, var(--slate) 9%, transparent);
--_knurl: color-mix(in oklab, var(--slate) 76%, var(--oat));
--_glow: color-mix(in oklab, var(--clay) 55%, transparent);
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body {
min-height: 100vh;
display: grid;
place-items: center;
background: var(--ivory);
color: var(--slate);
font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}
.plate {
position: relative;
width: var(--_s);
aspect-ratio: 1;
background: var(--paper);
border: 1px solid var(--oat);
border-radius: calc(28px * var(--round));
box-shadow: 0 1px 0 var(--paper) inset, 0 12px 28px var(--_shade-soft), 0 2px 4px var(--_shade-soft);
}
.well {
position: absolute;
inset: 0;
margin: auto;
width: 50%;
height: 50%;
border-radius: 50%;
background: var(--ivory);
box-shadow: inset 0 2px 5px var(--_shade-soft), inset 0 0 0 1px var(--oat);
}
/* The drop shadow sits on a static layer so it doesn't turn with the knob. */
.well::before,
.knob {
content: "";
position: absolute;
inset: 0;
margin: auto;
width: 84%;
height: 84%;
border-radius: 50%;
}
.well::before {
box-shadow: 0 6px 10px var(--_shade), 0 1px 2px var(--_shade);
}
.knob {
background: repeating-conic-gradient(var(--_knurl) 0deg 5deg, var(--slate) 5deg 10deg);
animation: turn var(--_loop) linear infinite;
}
.knob::before {
content: "";
position: absolute;
inset: 13%;
border-radius: 50%;
background: radial-gradient(circle, var(--paper) 0 45%, var(--oat) 100%);
box-shadow: 0 0 0 1px var(--slate);
}
.pointer {
position: absolute;
left: 50%;
top: 19%;
width: 6%;
height: 22%;
margin-left: -3%;
border-radius: 999px;
background: var(--clay);
}
.stop {
position: absolute;
left: 50%;
top: 50%;
transform: rotate(var(--_a)) translateY(calc(var(--_s) * -0.38)) rotate(calc(var(--_a) * -1));
}
.mark {
position: absolute;
left: 0;
top: 0;
transform: translate(-50%, -50%);
display: flex;
flex-direction: column;
align-items: center;
gap: 4px;
}
.led {
position: relative;
width: 7px;
height: 7px;
border-radius: 50%;
background: var(--oat);
box-shadow: inset 0 1px 1px var(--_shade-soft);
}
.led::after {
content: "";
position: absolute;
inset: 0;
border-radius: 50%;
background: var(--clay);
box-shadow: 0 0 6px var(--_glow);
opacity: 0;
animation: led var(--_loop) ease infinite;
animation-delay: calc(var(--_loop) * (var(--_i) * 0.25 - 1));
}
.label {
font-size: clamp(11px, calc(var(--_s) * 0.062), 13px);
font-weight: 600;
letter-spacing: 0.06em;
text-transform: uppercase;
line-height: 1;
opacity: 0.45;
animation: label var(--_loop) ease infinite;
animation-delay: calc(var(--_loop) * (var(--_i) * 0.25 - 1));
}
/* Each quarter: hold 17%, turn 8% (~288ms at speed 1) into the next detent. */
@keyframes turn {
0%, 17% { transform: rotate(0deg); }
25%, 42% { transform: rotate(90deg); }
50%, 67% { transform: rotate(180deg); }
75%, 92% { transform: rotate(270deg); }
100% { transform: rotate(360deg); }
}
/* The LED lights just after the knob lands and dims as it leaves. */
@keyframes led {
0% { opacity: 0; }
4%, 17% { opacity: 1; }
21%, 100% { opacity: 0; }
}
@keyframes label {
0% { opacity: 0.45; }
4%, 17% { opacity: 1; }
21%, 100% { opacity: 0.45; }
}
@keyframes led-calm {
0% { opacity: 0.2; }
8%, 17% { opacity: 0.9; }
25%, 100% { opacity: 0.2; }
}
@keyframes label-calm {
0% { opacity: 0.5; }
8%, 17% { opacity: 1; }
25%, 100% { opacity: 0.5; }
}
@media (max-width: 380px) {
:root { --_s: min(200px, 74vmin); }
}
@media (prefers-reduced-motion: reduce) {
:root { --_loop: calc(var(--t) * 2); }
.knob { animation: none; }
.pointer { opacity: 0; }
.led::after { animation-name: led-calm; }
.label { animation-name: label-calm; }
}
</style>
</head>
<body>
<div class="plate" role="img" aria-label="Speed dial stepping through Off, Low, Mid and High">
<div class="well">
<div class="knob"><span class="pointer"></span></div>
</div>
<div class="stop" style="--_i: 0; --_a: 0deg"><div class="mark"><span class="led"></span><span class="label">Off</span></div></div>
<div class="stop" style="--_i: 1; --_a: 90deg"><div class="mark"><span class="led"></span><span class="label">Low</span></div></div>
<div class="stop" style="--_i: 2; --_a: 180deg"><div class="mark"><span class="led"></span><span class="label">Mid</span></div></div>
<div class="stop" style="--_i: 3; --_a: 270deg"><div class="mark"><span class="led"></span><span class="label">High</span></div></div>
</div>
</body>
</html>
The variant family
Same idea, one axis moved. Compare them side by side before you commit.