03Volume slider popover

<main class="stage">
  <figure class="pl is-demo" id="pl">
    <div class="pl__screen">
      <div class="pl__stripes" aria-hidden="true"></div>
      <div class="pl__world" aria-hidden="true"><span class="pl__sun"></span><span class="pl__hill pl__hill--a"></span><span class="pl__hill pl__hill--b"></span></div>
      <span class="pl__clock" id="clock">1:24</span>
      <span class="pl__badge">3:00</span>
      <div class="vol">
        <button class="vol__btn" type="button" id="vbtn" aria-label="Volume control" aria-expanded="true" aria-controls="pop">
          <span class="vol__ic vol__ic--high" aria-hidden="true"><svg viewBox="0 0 256 256" width="18" height="18"><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>
          <span class="vol__ic vol__ic--low" aria-hidden="true"><svg viewBox="0 0 256 256" width="18" height="18"><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-56-43.55V91.91l56-43.55ZM208 128a39.93 39.93 0 0 1-10 26.46a8 8 0 0 1-12-10.58a24 24 0 0 0 0-31.72a8 8 0 1 1 12-10.58A40 40 0 0 1 208 128"/></g></svg></span>
          <span class="vol__ic vol__ic--mute" aria-hidden="true"><svg viewBox="0 0 256 256" width="18" height="18"><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-56-43.57V91.94l56-43.58Zm101.66-61.3a8 8 0 0 1-11.32 11.32L216 139.31l-18.34 18.35a8 8 0 0 1-11.32-11.32L204.69 128l-18.35-18.34a8 8 0 0 1 11.32-11.32L216 116.69l18.34-18.35a8 8 0 0 1 11.32 11.32L227.31 128Z"/></g></svg></span>
        </button>
        <div class="vol__pop" id="pop">
          <div class="vol__slider" id="vs" role="slider" tabindex="0" aria-label="Volume" aria-valuemin="0" aria-valuemax="100" aria-valuenow="80" aria-valuetext="80%">
            <span class="vol__track" aria-hidden="true">
              <span class="vol__fill"></span>
              <span class="vol__thumbwrap"><span class="vol__thumb"></span></span>
            </span>
          </div>
          <span class="vol__pct" id="pct">80</span>
        </div>
      </div>
      <span class="pl__time"><b id="t-now">1:24</b> / 3:00</span>
    </div>
  </figure>
</main>

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

@property --v { syntax: "<number>"; inherits: true; initial-value: 0.8; }

$duration: $dur-quick;
$easing: $ease-pop;
$color: $subject-ink;

@include stage($stage-orange);

.pl {
  position: relative;
  box-sizing: border-box;
  width: min(392px, 92vw);
  margin: 0;
  border-radius: $r-card;
  background: $subject-cream;
  box-shadow: $shadow-raised;
  overflow: hidden;
}
.pl__screen {
  position: relative;
  height: clamp(96px, 26vw, 140px);
  overflow: hidden;
  background: linear-gradient(180deg, rgba(47, 109, 246, .34), rgba(255, 247, 230, .96));
}
.pl__stripes {
  position: absolute; inset: 0 -72px;
  background: repeating-linear-gradient(90deg, rgba(23, 20, 26, .13) 0 12px, transparent 12px 32px);
  animation-name: pl-pan;
  animation-duration: $dur-loop;
  animation-timing-function: linear;
  animation-iteration-count: infinite;
}
@keyframes pl-pan { from { transform: translateX(0); } to { transform: translateX(-64px); } }
.pl__world { position: absolute; inset: 0; }
.pl__sun {
  position: absolute; right: 20%; top: 14%;
  width: 26px; height: 26px; border-radius: 50%;
  background: rgba(255, 210, 63, .95);
  box-shadow: 0 0 0 8px rgba(255, 210, 63, .25);
}
.pl__hill { position: absolute; bottom: -46%; height: 82%; border-radius: 50%; }
.pl__hill--a { left: -14%; width: 72%; background: rgba(23, 20, 26, .15); }
.pl__hill--b { right: -18%; width: 62%; background: rgba(23, 20, 26, .09); }
.pl__clock, .pl__badge {
  position: absolute; top: $sp-2;
  padding: $sp-1 $sp-2;
  border-radius: $r-xs;
  background: rgba(23, 20, 26, .62);
  font-family: ui-monospace, "Cascadia Mono", Menlo, Consolas, monospace;
  font-size: 10px; line-height: 14px; font-weight: 700;
}
.pl__clock { left: $sp-2; color: #fff; }
.pl__badge { right: $sp-2; color: rgba(255, 255, 255, .85); }
.pl__time {
  position: absolute; right: $sp-2; bottom: $sp-2;
  color: $subject-ink;   // 화면 아래쪽은 크림이라 흰 글자가 1.35~2.10:1 이었다 — 잉크로 8.69~13.49:1
  font-family: ui-monospace, "Cascadia Mono", Menlo, Consolas, monospace;
  font-size: 11px; line-height: 14px; font-weight: 600;
  text-shadow: 0 1px 2px rgba(255, 247, 230, .6);
}

.vol {
  position: absolute; left: $sp-2; bottom: $sp-2;
  display: flex; align-items: flex-end; gap: $sp-1;
}
.vol__pop {
  // 팝오버는 버튼 옆으로 절대 배치한다 — 흐름에 두면 닫혀 있을 때도 152px 자리를 잡아 버튼이 화면 한가운데로 밀린다
  position: absolute; left: calc(100% + #{$sp-1}); bottom: 0;
  display: flex; align-items: center; gap: $sp-2;
  box-sizing: border-box;
  width: 152px; height: 36px;
  padding: 0 $sp-2;
  border-radius: $r-control;
  background: rgba(23, 20, 26, .88);
  transform: translateX(-6px) scale(.6);
  transform-origin: left bottom; // 규칙8: 버튼 옆 변서 펼침
  opacity: 0;
  pointer-events: none;
  transition: transform $duration $easing, opacity $duration $easing;
}
.pl.is-open .vol__pop { transform: none; opacity: 1; pointer-events: auto; }
.vol__slider {
  --v: 0.8;
  position: relative;
  flex: 1 1 auto;
  height: 32px;
  cursor: pointer;
  touch-action: none;
}
.vol__slider:focus-visible { outline: 2px solid $stage-yellow; outline-offset: -2px; border-radius: $r-sm; }
.vol__track {
  position: absolute; left: 0; right: 0; top: 50%;
  height: 6px;
  margin-top: -3px;
  border-radius: $r-pill;
  background: rgba(255, 255, 255, .22);
}
.vol__fill {
  position: absolute; inset: 0;
  border-radius: $r-pill;
  background: rgba(255, 210, 63, .95);
  transform-origin: left center; // 규칙8: 좌변서 차오름
  transform: scaleX(var(--v));
}
.vol__thumbwrap {
  position: absolute; inset: 0;
  pointer-events: none;
  transform: translateX(calc((100% - 12px) * var(--v)));
}
.vol__thumb {
  position: absolute; left: 0; top: 50%;
  width: 12px; height: 12px;
  margin-top: -6px;
  border-radius: 50%;
  background: #fff;
  box-shadow: 0 2px 6px rgba(23, 20, 26, .5);
}
.vol__pct {
  flex: 0 0 auto;
  min-width: 20px;
  color: rgba(255, 255, 255, .9);
  font-family: ui-monospace, "Cascadia Mono", Menlo, Consolas, monospace;
  font-size: 10px; line-height: 12px; font-weight: 700;
  text-align: right;
}
.vol__btn {
  position: relative;
  box-sizing: border-box;
  width: 36px; height: 36px;
  flex: 0 0 auto;
  display: inline-flex; align-items: center; justify-content: center;
  border: 0;
  border-radius: $r-control;
  background: rgba(23, 20, 26, .72);
  color: #fff;
  cursor: pointer;
  transition: background $duration $easing;
}
.vol__btn:hover { background: rgba(23, 20, 26, .9); }
.vol__btn:focus-visible { outline: 2px solid $stage-yellow; outline-offset: 2px; }
.vol__ic { position: absolute; display: inline-flex; }
.vol__ic--low, .vol__ic--mute { display: none; }
.pl.is-low .vol__ic--high { display: none; }
.pl.is-low .vol__ic--low { display: inline-flex; }
.pl.is-mute .vol__ic--high, .pl.is-low .vol__ic--low { display: none; }
.pl.is-mute .vol__ic--mute { display: inline-flex; }

// ── 자동 루프: 팝오버가 열리고 음량이 내려가 0(뮤트)을 지나 다시 오른다. 아이콘 교체는 한 프레임 컷 ──
.pl.is-demo .vol__pop {
  animation-name: vol-pop;
  animation-duration: $dur-loop;
  animation-timing-function: $easing;
  animation-iteration-count: infinite;
}
.pl.is-demo .vol__slider {
  animation-name: vol-v;
  animation-duration: $dur-loop;
  animation-timing-function: ease-in-out;
  animation-iteration-count: infinite;
}
.pl.is-demo .vol__ic--high {
  animation-name: vol-i-high;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.pl.is-demo .vol__ic--low {
  display: inline-flex;
  animation-name: vol-i-low;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
.pl.is-demo .vol__ic--mute {
  display: inline-flex;
  animation-name: vol-i-mute;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
@keyframes vol-pop {
  0%, 6% { opacity: 0; transform: translateX(-6px) scale(.6); }
  16%, 80% { opacity: 1; transform: none; }
  88%, 100% { opacity: 0; transform: translateX(-6px) scale(.6); }
}
@keyframes vol-v {
  0%, 8% { --v: 0.8; }
  40% { --v: 0.22; }
  50%, 58% { --v: 0; }
  68% { --v: 0.3; }
  80%, 100% { --v: 0.8; }
}
@keyframes vol-i-high {
  0%, 36% { opacity: 1; }
  37%, 63% { opacity: 0; }
  64%, 100% { opacity: 1; }
}
@keyframes vol-i-low {
  0%, 36% { opacity: 0; }
  37%, 44% { opacity: 1; }
  45%, 66% { opacity: 0; }
  67%, 74% { opacity: 1; }
  75%, 100% { opacity: 0; }
}
@keyframes vol-i-mute {
  0%, 44% { opacity: 0; }
  45%, 58% { opacity: 1; }
  59%, 100% { opacity: 0; }
}
.pl.is-demo .vol__pct {
  animation-name: vol-pct;
  animation-duration: $dur-loop;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}
@keyframes vol-pct {
  0%, 8% { opacity: 1; }
  40% { opacity: 1; }
  50%, 58% { opacity: 1; }
  68% { opacity: 1; }
  80%, 100% { opacity: 1; }
}

@media (prefers-reduced-motion: reduce) {
  .pl.is-demo .vol__pop, .pl.is-demo .vol__slider, .pl.is-demo .vol__ic--high,
  .pl.is-demo .vol__ic--low, .pl.is-demo .vol__ic--mute, .pl.is-demo .vol__pct,
  .pl__stripes { animation: none !important; }
  .vol__pop { transition: none; }
}

@property --v {
  syntax: "<number>";
  inherits: true;
  initial-value: 0.8;
}
html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ff4d1f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.pl {
  position: relative;
  box-sizing: border-box;
  width: min(392px, 92vw);
  margin: 0;
  border-radius: 16px;
  background: #fff7e6;
  box-shadow: 0 14px 24px rgba(23, 20, 26, 0.32);
  overflow: hidden;
}

.pl__screen {
  position: relative;
  height: clamp(96px, 26vw, 140px);
  overflow: hidden;
  background: linear-gradient(180deg, rgba(47, 109, 246, 0.34), rgba(255, 247, 230, 0.96));
}

.pl__stripes {
  position: absolute;
  inset: 0 -72px;
  background: repeating-linear-gradient(90deg, rgba(23, 20, 26, 0.13) 0 12px, transparent 12px 32px);
  animation-name: pl-pan;
  animation-duration: 2s;
  animation-timing-function: linear;
  animation-iteration-count: infinite;
}

@keyframes pl-pan {
  from {
    transform: translateX(0);
  }
  to {
    transform: translateX(-64px);
  }
}
.pl__world {
  position: absolute;
  inset: 0;
}

.pl__sun {
  position: absolute;
  right: 20%;
  top: 14%;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: rgba(255, 210, 63, 0.95);
  box-shadow: 0 0 0 8px rgba(255, 210, 63, 0.25);
}

.pl__hill {
  position: absolute;
  bottom: -46%;
  height: 82%;
  border-radius: 50%;
}

.pl__hill--a {
  left: -14%;
  width: 72%;
  background: rgba(23, 20, 26, 0.15);
}

.pl__hill--b {
  right: -18%;
  width: 62%;
  background: rgba(23, 20, 26, 0.09);
}

.pl__clock, .pl__badge {
  position: absolute;
  top: 8px;
  padding: 4px 8px;
  border-radius: 4px;
  background: rgba(23, 20, 26, 0.62);
  font-family: ui-monospace, "Cascadia Mono", Menlo, Consolas, monospace;
  font-size: 10px;
  line-height: 14px;
  font-weight: 700;
}

.pl__clock {
  left: 8px;
  color: #fff;
}

.pl__badge {
  right: 8px;
  color: rgba(255, 255, 255, 0.85);
}

.pl__time {
  position: absolute;
  right: 8px;
  bottom: 8px;
  color: #17141a;
  font-family: ui-monospace, "Cascadia Mono", Menlo, Consolas, monospace;
  font-size: 11px;
  line-height: 14px;
  font-weight: 600;
  text-shadow: 0 1px 2px rgba(255, 247, 230, 0.6);
}

.vol {
  position: absolute;
  left: 8px;
  bottom: 8px;
  display: flex;
  align-items: flex-end;
  gap: 4px;
}

.vol__pop {
  position: absolute;
  left: calc(100% + 4px);
  bottom: 0;
  display: flex;
  align-items: center;
  gap: 8px;
  box-sizing: border-box;
  width: 152px;
  height: 36px;
  padding: 0 8px;
  border-radius: 12px;
  background: rgba(23, 20, 26, 0.88);
  transform: translateX(-6px) scale(0.6);
  transform-origin: left bottom;
  opacity: 0;
  pointer-events: none;
  transition: transform 220ms cubic-bezier(0.2, 1.4, 0.4, 1), opacity 220ms cubic-bezier(0.2, 1.4, 0.4, 1);
}

.pl.is-open .vol__pop {
  transform: none;
  opacity: 1;
  pointer-events: auto;
}

.vol__slider {
  --v: 0.8;
  position: relative;
  flex: 1 1 auto;
  height: 32px;
  cursor: pointer;
  touch-action: none;
}

.vol__slider:focus-visible {
  outline: 2px solid #ffd23f;
  outline-offset: -2px;
  border-radius: 8px;
}

.vol__track {
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 6px;
  margin-top: -3px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.22);
}

.vol__fill {
  position: absolute;
  inset: 0;
  border-radius: 999px;
  background: rgba(255, 210, 63, 0.95);
  transform-origin: left center;
  transform: scaleX(var(--v));
}

.vol__thumbwrap {
  position: absolute;
  inset: 0;
  pointer-events: none;
  transform: translateX(calc((100% - 12px) * var(--v)));
}

.vol__thumb {
  position: absolute;
  left: 0;
  top: 50%;
  width: 12px;
  height: 12px;
  margin-top: -6px;
  border-radius: 50%;
  background: #fff;
  box-shadow: 0 2px 6px rgba(23, 20, 26, 0.5);
}

.vol__pct {
  flex: 0 0 auto;
  min-width: 20px;
  color: rgba(255, 255, 255, 0.9);
  font-family: ui-monospace, "Cascadia Mono", Menlo, Consolas, monospace;
  font-size: 10px;
  line-height: 12px;
  font-weight: 700;
  text-align: right;
}

.vol__btn {
  position: relative;
  box-sizing: border-box;
  width: 36px;
  height: 36px;
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 0;
  border-radius: 12px;
  background: rgba(23, 20, 26, 0.72);
  color: #fff;
  cursor: pointer;
  transition: background 220ms cubic-bezier(0.2, 1.4, 0.4, 1);
}

.vol__btn:hover {
  background: rgba(23, 20, 26, 0.9);
}

.vol__btn:focus-visible {
  outline: 2px solid #ffd23f;
  outline-offset: 2px;
}

.vol__ic {
  position: absolute;
  display: inline-flex;
}

.vol__ic--low, .vol__ic--mute {
  display: none;
}

.pl.is-low .vol__ic--high {
  display: none;
}

.pl.is-low .vol__ic--low {
  display: inline-flex;
}

.pl.is-mute .vol__ic--high, .pl.is-low .vol__ic--low {
  display: none;
}

.pl.is-mute .vol__ic--mute {
  display: inline-flex;
}

.pl.is-demo .vol__pop {
  animation-name: vol-pop;
  animation-duration: 2s;
  animation-timing-function: cubic-bezier(0.2, 1.4, 0.4, 1);
  animation-iteration-count: infinite;
}

.pl.is-demo .vol__slider {
  animation-name: vol-v;
  animation-duration: 2s;
  animation-timing-function: ease-in-out;
  animation-iteration-count: infinite;
}

.pl.is-demo .vol__ic--high {
  animation-name: vol-i-high;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.pl.is-demo .vol__ic--low {
  display: inline-flex;
  animation-name: vol-i-low;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

.pl.is-demo .vol__ic--mute {
  display: inline-flex;
  animation-name: vol-i-mute;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

@keyframes vol-pop {
  0%, 6% {
    opacity: 0;
    transform: translateX(-6px) scale(0.6);
  }
  16%, 80% {
    opacity: 1;
    transform: none;
  }
  88%, 100% {
    opacity: 0;
    transform: translateX(-6px) scale(0.6);
  }
}
@keyframes vol-v {
  0%, 8% {
    --v: 0.8;
  }
  40% {
    --v: 0.22;
  }
  50%, 58% {
    --v: 0;
  }
  68% {
    --v: 0.3;
  }
  80%, 100% {
    --v: 0.8;
  }
}
@keyframes vol-i-high {
  0%, 36% {
    opacity: 1;
  }
  37%, 63% {
    opacity: 0;
  }
  64%, 100% {
    opacity: 1;
  }
}
@keyframes vol-i-low {
  0%, 36% {
    opacity: 0;
  }
  37%, 44% {
    opacity: 1;
  }
  45%, 66% {
    opacity: 0;
  }
  67%, 74% {
    opacity: 1;
  }
  75%, 100% {
    opacity: 0;
  }
}
@keyframes vol-i-mute {
  0%, 44% {
    opacity: 0;
  }
  45%, 58% {
    opacity: 1;
  }
  59%, 100% {
    opacity: 0;
  }
}
.pl.is-demo .vol__pct {
  animation-name: vol-pct;
  animation-duration: 2s;
  animation-timing-function: steps(1, end);
  animation-iteration-count: infinite;
}

@keyframes vol-pct {
  0%, 8% {
    opacity: 1;
  }
  40% {
    opacity: 1;
  }
  50%, 58% {
    opacity: 1;
  }
  68% {
    opacity: 1;
  }
  80%, 100% {
    opacity: 1;
  }
}
@media (prefers-reduced-motion: reduce) {
  .pl.is-demo .vol__pop, .pl.is-demo .vol__slider, .pl.is-demo .vol__ic--high,
  .pl.is-demo .vol__ic--low, .pl.is-demo .vol__ic--mute, .pl.is-demo .vol__pct,
  .pl__stripes {
    animation: none !important;
  }
  .vol__pop {
    transition: none;
  }
}

// 실제 동작: 버튼으로 슬라이더를 여닫고, 끌거나 화살표로 음량을 바꾸면 아이콘이 바뀐다.
var root = document.getElementById('pl'),
    btn = document.getElementById('vbtn'),
    pop = document.getElementById('pop'),
    vs = document.getElementById('vs'),
    pct = document.getElementById('pct'),
    clock = document.getElementById('clock'),
    now = document.getElementById('t-now');
var DUR = 180, t = 84, v = 0.8;
function fmt(s) { s = Math.floor(s); return Math.floor(s / 60) + ':' + ('0' + (s % 60)).slice(-2); }
setInterval(function () {
  t = (t + .5) % DUR;
  clock.textContent = fmt(t);
  now.textContent = fmt(t);
}, 500);
function paint() {
  vs.style.setProperty('--v', v.toFixed(3));
  vs.setAttribute('aria-valuenow', Math.round(v * 100));
  vs.setAttribute('aria-valuetext', Math.round(v * 100) + '%');
  pct.textContent = Math.round(v * 100);
  root.classList.toggle('is-mute', v === 0);
  root.classList.toggle('is-low', v > 0 && v < 0.5);
}
function open(on) {
  root.classList.remove('is-demo');
  root.classList.toggle('is-open', on);
  btn.setAttribute('aria-expanded', String(on));
  if (on) vs.focus({ preventScroll: true });
}
btn.addEventListener('click', function () { open(!root.classList.contains('is-open')); });
function pos(e) {
  var r = vs.getBoundingClientRect();
  return Math.max(0, Math.min(1, (e.clientX - r.left) / r.width));
}
function set(p) { v = Math.round(p * 20) / 20; paint(); }
vs.addEventListener('pointerdown', function (e) { vs.setPointerCapture(e.pointerId); root.classList.remove('is-demo'); set(pos(e)); });
vs.addEventListener('pointermove', function (e) { if (e.buttons) set(pos(e)); });
vs.addEventListener('keydown', function (e) {
  if (e.key === 'ArrowRight') { v = Math.min(1, v + .1); paint(); e.preventDefault(); }
  else if (e.key === 'ArrowLeft') { v = Math.max(0, v - .1); paint(); e.preventDefault(); }
  else if (e.key === 'Home') { v = 0; paint(); e.preventDefault(); }
  else if (e.key === 'End') { v = 1; paint(); e.preventDefault(); }
});
document.addEventListener('click', function (e) { if (!e.target.closest('.vol')) open(false); });

import { useEffect, useRef, useState } from "react";
import type { CSSProperties } from "react";
import styles from "./VolumePopover.module.scss";

export type VolumePopoverProps = {
  /** 더미 영상 길이(초) */
  total?: number;
  /** 시작 위치(초) */
  start?: number;
  /** 시작 음량 0~1 */
  initialVolume?: number;
  duration?: number;
  easing?: string;
  color?: string;
};

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

// TS7006 방지 — 'react' 의 이벤트 제네릭 대신 필요한 필드만 로컬로 선언한다
type Rect = { left: number; width: number };
type PtrEvt = {
  clientX: number;
  buttons: number;
  pointerId: number;
  currentTarget: { getBoundingClientRect: () => Rect; setPointerCapture: (id: number) => void };
};
type KeyEvt = { key: string; preventDefault: () => void };

function fmt(s: number) {
  const n = Math.floor(s);
  return Math.floor(n / 60) + ":" + ("0" + (n % 60)).slice(-2);
}

function HighIcon() {
  return (
    <svg viewBox="0 0 256 256" width="18" height="18" aria-hidden="true">
      <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>
  );
}

function LowIcon() {
  return (
    <svg viewBox="0 0 256 256" width="18" height="18" aria-hidden="true">
      <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-56-43.55V91.91l56-43.55ZM208 128a39.93 39.93 0 0 1-10 26.46a8 8 0 0 1-12-10.58a24 24 0 0 0 0-31.72a8 8 0 1 1 12-10.58A40 40 0 0 1 208 128" />
      </g>
    </svg>
  );
}

function MuteIcon() {
  return (
    <svg viewBox="0 0 256 256" width="18" height="18" aria-hidden="true">
      <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-56-43.57V91.94l56-43.58Zm101.66-61.3a8 8 0 0 1-11.32 11.32L216 139.31l-18.34 18.35a8 8 0 0 1-11.32-11.32L204.69 128l-18.35-18.34a8 8 0 0 1 11.32-11.32L216 116.69l18.34-18.35a8 8 0 0 1 11.32 11.32L227.31 128Z" />
      </g>
    </svg>
  );
}

export default function VolumePopover({
  total = 180,
  start = 84,
  initialVolume = 0.8,
  duration = 220,
  easing = "cubic-bezier(.2,1.4,.4,1)",
  color = "#ffd23f",
}: VolumePopoverProps) {
  const [open, setOpen] = useState(false);
  const [v, setV] = useState(initialVolume);
  const [t, setT] = useState(start);
  const volRef = useRef<HTMLDivElement>(null);
  const sliderRef = useRef<HTMLDivElement>(null);
  const vars: Vars = { "--duration": `${duration}ms`, "--easing": easing, "--color": color };
  const sliderVars: SliderVars = { "--v": v.toFixed(3) };

  // 더미 재생 시계 — 바닐라의 setInterval(500ms, +0.5초) 을 그대로
  useEffect(() => {
    const id = setInterval(() => setT((p) => (p + 0.5) % total), 500);
    return () => clearInterval(id);
  }, [total]);

  // 바깥을 누르면 닫는다
  useEffect(() => {
    function onDocClick(e: MouseEvent) {
      if (volRef.current && !volRef.current.contains(e.target as Node)) setOpen(false);
    }
    document.addEventListener("click", onDocClick);
    return () => document.removeEventListener("click", onDocClick);
  }, []);

  useEffect(() => {
    if (open) sliderRef.current?.focus({ preventScroll: true });
  }, [open]);

  function set(e: PtrEvt) {
    const r = e.currentTarget.getBoundingClientRect();
    const p = Math.max(0, Math.min(1, (e.clientX - r.left) / r.width));
    setV(Math.round(p * 20) / 20);
  }

  const pct = Math.round(v * 100);
  const state = v === 0 ? styles.isMute : v < 0.5 ? styles.isLow : "";

  return (
    <figure className={`${styles.player} ${open ? styles.isOpen : ""} ${state}`} style={vars}>
      <div className={styles.screen}>
        <div className={styles.stripes} aria-hidden="true" />
        <div className={styles.world} aria-hidden="true">
          <span className={styles.sun} />
          <span className={`${styles.hill} ${styles.hillA}`} />
          <span className={`${styles.hill} ${styles.hillB}`} />
        </div>
        <span className={styles.clock}>{fmt(t)}</span>
        <span className={styles.badge}>{fmt(total)}</span>
        <div className={styles.vol} ref={volRef}>
          <button
            className={styles.btn}
            type="button"
            aria-label="음량 조절"
            aria-expanded={open}
            aria-controls="vol-pop"
            onClick={() => setOpen((o) => !o)}
          >
            <span className={`${styles.ic} ${styles.icHigh}`}>
              <HighIcon />
            </span>
            <span className={`${styles.ic} ${styles.icLow}`}>
              <LowIcon />
            </span>
            <span className={`${styles.ic} ${styles.icMute}`}>
              <MuteIcon />
            </span>
          </button>
          <div className={styles.pop} id="vol-pop">
            <div
              ref={sliderRef}
              className={styles.slider}
              style={sliderVars}
              role="slider"
              tabIndex={0}
              aria-label="음량"
              aria-valuemin={0}
              aria-valuemax={100}
              aria-valuenow={pct}
              aria-valuetext={`${pct}%`}
              onPointerDown={(e: PtrEvt) => {
                e.currentTarget.setPointerCapture(e.pointerId);
                set(e);
              }}
              onPointerMove={(e: PtrEvt) => {
                if (e.buttons) set(e);
              }}
              onKeyDown={(e: KeyEvt) => {
                if (e.key === "ArrowRight") { setV((p) => Math.min(1, p + 0.1)); e.preventDefault(); }
                else if (e.key === "ArrowLeft") { setV((p) => Math.max(0, p - 0.1)); e.preventDefault(); }
                else if (e.key === "Home") { setV(0); e.preventDefault(); }
                else if (e.key === "End") { setV(1); e.preventDefault(); }
              }}
            >
              <span className={styles.track} aria-hidden="true">
                <span className={styles.fill} />
                <span className={styles.thumbwrap}>
                  <span className={styles.thumb} />
                </span>
              </span>
            </div>
            <span className={styles.pct}>{pct}</span>
          </div>
        </div>
        <span className={styles.time}>
          <b>{fmt(t)}</b> / {fmt(total)}
        </span>
      </div>
    </figure>
  );
}