04Volume knob widget

<main class="stage">
  <section class="volknob" aria-label="Volume knob">
    <span class="volknob__icon" aria-hidden="true">
      <svg xmlns="http://www.w3.org/2000/svg" width="1em" height="1em" viewBox="0 0 256 256"><g fill="currentColor"><path d="M80 88v80H32a8 8 0 0 1-8-8V96a8 8 0 0 1 8-8Z" opacity=".2"/><path d="M155.51 24.81a8 8 0 0 0-8.42.88L77.25 80H32a16 16 0 0 0-16 16v64a16 16 0 0 0 16 16h45.25l69.84 54.31A8 8 0 0 0 160 224V32a8 8 0 0 0-4.49-7.19M32 96h40v64H32Zm112 111.64l-56-43.55V91.91l56-43.55Zm54-106.08a40 40 0 0 1 0 52.88a8 8 0 0 1-12-10.58a24 24 0 0 0 0-31.72a8 8 0 0 1 12-10.58M248 128a79.9 79.9 0 0 1-20.37 53.34a8 8 0 0 1-11.92-10.67a64 64 0 0 0 0-85.33a8 8 0 1 1 11.92-10.67A79.83 79.83 0 0 1 248 128"/></g></svg>
    </span>
    <div class="volknob__panel">
      <span class="volknob__tick volknob__tick--1" aria-hidden="true"></span>
      <span class="volknob__tick volknob__tick--2" aria-hidden="true"></span>
      <span class="volknob__tick volknob__tick--3" aria-hidden="true"></span>
      <span class="volknob__tick volknob__tick--4" aria-hidden="true"></span>
      <span class="volknob__tick volknob__tick--5" aria-hidden="true"></span>
      <div class="volknob__knob">
        <span class="volknob__needle" aria-hidden="true"></span>
      </div>
    </div>
    <p class="volknob__label">Volume</p>
  </section>
</main>

@use "../../../../site/static/demo-tokens" as *;

// 스큐어모픽 볼륨 노브 — 어두운 몸통에 밝은 지침. 몸통이 돌면 위 하이라이트 대비로 회전이 읽힌다
$knob-body:  #2b2831;   // 노브 몸통
$knob-face:  #38343f;   // 노브 윗면
$knob-line:  #efe8f7;   // 지침 선 (밝게)
$panel-bg:   #eceaf1;   // 눈금 판

$duration: $dur-loop;   // 최소 → 최대 → 최소 한 주기
$easing: $ease-out;     // 손을 떼면 감속하며 멈춘다
$color: $knob-body;

@include stage($stage-paper);

.volknob {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: $sp-2;
}

.volknob__icon {
  width: 28px;
  height: 28px;
  color: $subject-ink;
}

// 눈금 판 — 눈금 다섯 개를 원주 위에 미리 돌려 놓는다 (정적)
.volknob__panel {
  position: relative;
  width: clamp(132px, 42vw, 176px);
  aspect-ratio: 1;
  border-radius: 50%;
  background: radial-gradient(130% 130% at 30% 24%, #ffffff, $panel-bg 70%);
  box-shadow: inset 0 2px 4px rgba(23, 20, 26, .18), 0 3px 8px rgba(23, 20, 26, .14);
}
.volknob__tick {
  position: absolute;
  top: 6px; left: calc(50% - 2px);
  width: 4px;
  height: 10px;
  border-radius: $r-pill;
  background: #a9a4b4;
  transform-origin: 50% calc(clamp(66px, 21vw, 88px) - 11px);   // 패널 중심까지 = 반지름 - 눈금 중심 y
}
.volknob__tick--1 { transform: rotate(-120deg); }
.volknob__tick--2 { transform: rotate(-60deg); }
.volknob__tick--3 { transform: rotate(0deg); }
.volknob__tick--4 { transform: rotate(60deg); }
.volknob__tick--5 { transform: rotate(120deg); }

// 노브 몸통 — 도는 주인공. 윗면 그라디언트가 살짝 비스듬해 회전이 읽힌다
.volknob__knob {
  position: absolute;
  top: 20%; left: 20%; right: 20%; bottom: 20%;
  border-radius: 50%;
  background:
    radial-gradient(120% 120% at 34% 26%, rgba(255, 255, 255, .32), transparent 42%),
    conic-gradient(from 250deg, $knob-face, $knob-body 90deg, $knob-face 170deg, $knob-body 260deg, $knob-face 340deg);
  box-shadow: 0 6px 10px rgba(23, 20, 26, .35), inset 0 1px 2px rgba(255, 255, 255, .22);
  animation: knobSweep $duration $easing infinite;
}
.volknob__knob:focus-visible {
  outline: 3px solid $subject-blue;
  outline-offset: 3px;
}

// 지침 선 — 노브 안에서 위로 뻗는다
.volknob__needle {
  position: absolute;
  top: 6%; left: calc(50% - 2px);
  width: 4px;
  height: 30%;
  border-radius: $r-pill;
  background: $knob-line;
  box-shadow: 0 0 0 1px rgba(0, 0, 0, .3);
}

.volknob__label {
  margin: 0;
  color: $subject-ink;
  font-weight: 700; font-size: clamp(11px, 2.8vw, 13px); line-height: 1;
  font-family: inherit;
}

// 최소 눈금(-120도) 에서 최대(+120도) 까지 돌고 돌아온다 — 양 끝에서 잠시 멈춘다
@keyframes knobSweep {
  0%, 8%    { transform: rotate(-120deg); }
  46%, 56%  { transform: rotate(120deg); }
  92%, 100% { transform: rotate(-120deg); }
}

@media (max-width: 340px), (max-height: 220px) {
  .volknob__icon { width: 20px; height: 20px; }
  .volknob__label { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  .volknob__knob { animation: none !important; transform: none; }
}

html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ffffff;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.volknob {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.volknob__icon {
  width: 28px;
  height: 28px;
  color: #17141a;
}

.volknob__panel {
  position: relative;
  width: clamp(132px, 42vw, 176px);
  aspect-ratio: 1;
  border-radius: 50%;
  background: radial-gradient(130% 130% at 30% 24%, #ffffff, #eceaf1 70%);
  box-shadow: inset 0 2px 4px rgba(23, 20, 26, 0.18), 0 3px 8px rgba(23, 20, 26, 0.14);
}

.volknob__tick {
  position: absolute;
  top: 6px;
  left: calc(50% - 2px);
  width: 4px;
  height: 10px;
  border-radius: 999px;
  background: #a9a4b4;
  transform-origin: 50% calc(clamp(66px, 21vw, 88px) - 11px);
}

.volknob__tick--1 {
  transform: rotate(-120deg);
}

.volknob__tick--2 {
  transform: rotate(-60deg);
}

.volknob__tick--3 {
  transform: rotate(0deg);
}

.volknob__tick--4 {
  transform: rotate(60deg);
}

.volknob__tick--5 {
  transform: rotate(120deg);
}

.volknob__knob {
  position: absolute;
  top: 20%;
  left: 20%;
  right: 20%;
  bottom: 20%;
  border-radius: 50%;
  background: radial-gradient(120% 120% at 34% 26%, rgba(255, 255, 255, 0.32), transparent 42%), conic-gradient(from 250deg, #38343f, #2b2831 90deg, #38343f 170deg, #2b2831 260deg, #38343f 340deg);
  box-shadow: 0 6px 10px rgba(23, 20, 26, 0.35), inset 0 1px 2px rgba(255, 255, 255, 0.22);
  animation: knobSweep 2s ease-out infinite;
}

.volknob__knob:focus-visible {
  outline: 3px solid #2f6df6;
  outline-offset: 3px;
}

.volknob__needle {
  position: absolute;
  top: 6%;
  left: calc(50% - 2px);
  width: 4px;
  height: 30%;
  border-radius: 999px;
  background: #efe8f7;
  box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.3);
}

.volknob__label {
  margin: 0;
  color: #17141a;
  font-weight: 700;
  font-size: clamp(11px, 2.8vw, 13px);
  line-height: 1;
  font-family: inherit;
}

@keyframes knobSweep {
  0%, 8% {
    transform: rotate(-120deg);
  }
  46%, 56% {
    transform: rotate(120deg);
  }
  92%, 100% {
    transform: rotate(-120deg);
  }
}
@media (max-width: 340px), (max-height: 220px) {
  .volknob__icon {
    width: 20px;
    height: 20px;
  }
  .volknob__label {
    display: none;
  }
}
@media (prefers-reduced-motion: reduce) {
  .volknob__knob {
    animation: none !important;
    transform: none;
  }
}

import type { CSSProperties } from "react";
import styles from "./VolumeKnob.module.scss";

export type VolumeKnobProps = {
  label?: string;
  /** 스크린리더용 섹션 이름 (기본 "볼륨 노브") */
  ariaLabel?: string;
  /** 한 주기(기본 2000ms) */
  duration?: number;
  easing?: string;
  color?: string;
};

type Vars = CSSProperties & { "--duration"?: string; "--easing"?: string; "--color"?: string };

export default function VolumeKnob({
  label = "음량 조절",
  ariaLabel = "볼륨 노브",
  duration = 2000,
  easing = "ease-out",
  color = "#2b2831",
}: VolumeKnobProps) {
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };

  return (
    <section className={styles.volknob} style={vars} aria-label={ariaLabel}>
      <span className={styles.icon} aria-hidden="true">
        <svg xmlns="http://www.w3.org/2000/svg" width="1em" height="1em" viewBox="0 0 256 256"><g fill="currentColor"><path d="M80 88v80H32a8 8 0 0 1-8-8V96a8 8 0 0 1 8-8Z" opacity=".2"/><path d="M155.51 24.81a8 8 0 0 0-8.42.88L77.25 80H32a16 16 0 0 0-16 16v64a16 16 0 0 0 16 16h45.25l69.84 54.31A8 8 0 0 0 160 224V32a8 8 0 0 0-4.49-7.19M32 96h40v64H32Zm112 111.64l-56-43.55V91.91l56-43.55Zm54-106.08a40 40 0 0 1 0 52.88a8 8 0 0 1-12-10.58a24 24 0 0 0 0-31.72a8 8 0 0 1 12-10.58M248 128a79.9 79.9 0 0 1-20.37 53.34a8 8 0 0 1-11.92-10.67a64 64 0 0 0 0-85.33a8 8 0 1 1 11.92-10.67A79.83 79.83 0 0 1 248 128"/></g></svg>
      </span>
      <div className={styles.panel}>
        <span className={`${styles.tick} ${styles.tick1}`} aria-hidden="true" />
        <span className={`${styles.tick} ${styles.tick2}`} aria-hidden="true" />
        <span className={`${styles.tick} ${styles.tick3}`} aria-hidden="true" />
        <span className={`${styles.tick} ${styles.tick4}`} aria-hidden="true" />
        <span className={`${styles.tick} ${styles.tick5}`} aria-hidden="true" />
        <div className={styles.knob}>
          <span className={styles.needle} aria-hidden="true" />
        </div>
      </div>
      <p className={styles.label}>{label}</p>
    </section>
  );
}