Music — Waveform / Progress Scrubber

:root {
  --bg: #0b0b0f;
  --bg-2: #13131a;
  --surface: #1a1a22;
  --surface-2: #22222c;
  --text: #f4f4f7;
  --muted: #a0a0ad;
  --line: rgba(255, 255, 255, 0.1);
  --line-2: rgba(255, 255, 255, 0.18);
  --accent: #1db954;
  --accent-2: #8b5cf6;
  --accent-3: #ff3d71;
  --r-sm: 8px;
  --r-md: 14px;
  --r-lg: 20px;
  --r-full: 999px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.55);
  --display: "Space Grotesk", "Inter", system-ui, sans-serif;
  --body: "Inter", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  min-height: 100vh;
  background:
    radial-gradient(1100px 620px at 78% -8%, rgba(139, 92, 246, 0.16), transparent 60%),
    radial-gradient(900px 540px at 8% 108%, rgba(29, 185, 84, 0.12), transparent 58%),
    var(--bg);
  color: var(--text);
  font-family: var(--body);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  padding: clamp(16px, 4vw, 48px);
  display: flex;
  justify-content: center;
}

.ico {
  width: 18px;
  height: 18px;
  fill: currentColor;
  flex: none;
}

/* ---------------- stage ---------------- */
.stage {
  width: 100%;
  max-width: 760px;
}

.stage__head {
  margin-bottom: 26px;
}

.kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  background: rgba(29, 185, 84, 0.12);
  border: 1px solid rgba(29, 185, 84, 0.28);
  padding: 5px 12px;
  border-radius: var(--r-full);
}

.stage__title {
  font-family: var(--display);
  font-weight: 700;
  font-size: clamp(28px, 6vw, 46px);
  letter-spacing: -0.02em;
  margin: 14px 0 8px;
}

.stage__sub {
  color: var(--muted);
  max-width: 56ch;
  margin: 0;
  font-size: 15px;
}

/* ---------------- player ---------------- */
.player {
  position: relative;
  background: linear-gradient(180deg, var(--surface), var(--bg-2));
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow);
  padding: clamp(18px, 3vw, 28px);
  overflow: hidden;
}

.player::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2), var(--accent-3));
  opacity: 0.8;
}

.player__top {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-bottom: 24px;
}

/* CSS-drawn album cover */
.cover {
  position: relative;
  width: 92px;
  height: 92px;
  border-radius: var(--r-md);
  overflow: hidden;
  flex: none;
  background: linear-gradient(135deg, #1f2937, #0f172a);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.cover[data-theme="reservoir"] {
  background: linear-gradient(140deg, #0f2a3f, #143b5a 45%, #1db98a);
}

.cover__shape {
  position: absolute;
  border-radius: 50%;
  filter: blur(2px);
  mix-blend-mode: screen;
}

.cover__shape--1 {
  width: 70px;
  height: 70px;
  left: -16px;
  bottom: -20px;
  background: radial-gradient(circle, rgba(29, 185, 84, 0.95), transparent 70%);
}

.cover__shape--2 {
  width: 56px;
  height: 56px;
  right: -10px;
  top: -12px;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.9), transparent 70%);
}

.cover__ring {
  position: absolute;
  inset: 30%;
  border-radius: 50%;
  border: 2px solid rgba(255, 255, 255, 0.35);
  box-shadow: inset 0 0 0 6px rgba(255, 255, 255, 0.08);
}

.meta {
  min-width: 0;
  flex: 1;
}

.meta__badge {
  display: inline-block;
  font-size: 10.5px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: var(--r-full);
  padding: 3px 9px;
  margin-bottom: 8px;
}

.meta__title {
  font-family: var(--display);
  font-weight: 700;
  font-size: clamp(20px, 4vw, 26px);
  margin: 0 0 2px;
  letter-spacing: -0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.meta__artist {
  margin: 0 0 8px;
  color: var(--accent);
  font-weight: 600;
  font-size: 14px;
}

.meta__stats {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  color: var(--muted);
  font-size: 12.5px;
}

.stat {
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

.stat .ico {
  width: 13px;
  height: 13px;
  opacity: 0.8;
}

.like {
  flex: none;
  width: 44px;
  height: 44px;
  border-radius: var(--r-full);
  border: 1px solid var(--line);
  background: var(--surface-2);
  color: var(--muted);
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: transform 0.15s ease, color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.like:hover {
  color: var(--text);
  border-color: var(--line-2);
}

.like[aria-pressed="true"] {
  color: var(--accent-3);
  border-color: rgba(255, 61, 113, 0.5);
  background: rgba(255, 61, 113, 0.12);
}

.like:active {
  transform: scale(0.9);
}

/* ---------------- scrubber ---------------- */
.scrub {
  position: relative;
  height: 86px;
  margin: 6px 0 18px;
  cursor: pointer;
  touch-action: none;
  outline: none;
}

.scrub:focus-visible {
  box-shadow: 0 0 0 2px var(--bg), 0 0 0 4px var(--accent-2);
  border-radius: var(--r-sm);
}

.scrub__bars {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  gap: 2px;
  height: 100%;
}

.bar {
  flex: 1 1 0;
  min-width: 2px;
  border-radius: 2px;
  background: var(--surface-2);
  position: relative;
  transition: background 0.12s linear, transform 0.12s ease;
}

/* played portion */
.bar.is-played {
  background: linear-gradient(180deg, var(--accent), #15863e);
}

/* the bar currently passing under the playhead pulses */
.bar.is-cursor {
  background: linear-gradient(180deg, #4cf08a, var(--accent));
  transform: scaleY(1.06);
}

.scrub:hover .bar:not(.is-played) {
  background: #2c2c39;
}

.scrub__head {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 2px;
  background: #eafff2;
  box-shadow: 0 0 10px rgba(29, 185, 84, 0.9);
  transform: translateX(-50%);
  left: 0;
  pointer-events: none;
  z-index: 3;
}

.scrub__head::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #eafff2;
  transform: translate(-50%, -50%);
  box-shadow: 0 0 10px rgba(29, 185, 84, 0.9);
}

.scrub__hover {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 1px;
  background: var(--line-2);
  left: 0;
  transform: translateX(-50%);
  opacity: 0;
  pointer-events: none;
  z-index: 2;
}

.scrub.is-hovering .scrub__hover {
  opacity: 1;
}

.scrub__tip {
  position: absolute;
  bottom: calc(100% + 8px);
  left: 0;
  transform: translateX(-50%);
  background: var(--text);
  color: var(--bg);
  font-size: 11px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  padding: 3px 7px;
  border-radius: var(--r-sm);
  opacity: 0;
  transition: opacity 0.12s ease;
  pointer-events: none;
  white-space: nowrap;
  z-index: 4;
}

.scrub__tip::after {
  content: "";
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 5px solid transparent;
  border-top-color: var(--text);
}

.scrub.is-hovering .scrub__tip,
.scrub.is-dragging .scrub__tip {
  opacity: 1;
}

/* ---------------- controls ---------------- */
.controls {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.controls__left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.iconbtn {
  width: 40px;
  height: 40px;
  border-radius: var(--r-full);
  border: 1px solid var(--line);
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: color 0.18s ease, border-color 0.18s ease, transform 0.12s ease;
}

.iconbtn:hover {
  color: var(--text);
  border-color: var(--line-2);
}

.iconbtn:active {
  transform: scale(0.92);
}

.playbtn {
  width: 56px;
  height: 56px;
  border-radius: var(--r-full);
  border: none;
  cursor: pointer;
  background: linear-gradient(135deg, var(--accent), #16a34a);
  color: #03130a;
  display: grid;
  place-items: center;
  box-shadow: 0 8px 24px rgba(29, 185, 84, 0.4);
  transition: transform 0.14s ease, box-shadow 0.2s ease;
}

.playbtn:hover {
  transform: scale(1.05);
}

.playbtn:active {
  transform: scale(0.95);
}

.playbtn__icon {
  width: 26px;
  height: 26px;
  fill: currentColor;
}

.playbtn__pause {
  display: none;
}

.playbtn[aria-pressed="true"] .playbtn__play {
  display: none;
}

.playbtn[aria-pressed="true"] .playbtn__pause {
  display: block;
}

.controls__time {
  display: flex;
  align-items: center;
  gap: 6px;
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  font-size: 14px;
}

.time--current {
  color: var(--text);
}

.time--total,
.time__sep {
  color: var(--muted);
}

.controls__speed {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 12px;
}

/* equalizer */
.eq {
  display: inline-flex;
  align-items: flex-end;
  gap: 3px;
  height: 20px;
}

.eq i {
  width: 3px;
  height: 6px;
  border-radius: 2px;
  background: var(--muted);
  transition: background 0.2s ease;
}

.eq.is-on i {
  background: var(--accent);
  animation: eq 0.9s ease-in-out infinite;
}

.eq.is-on i:nth-child(2) {
  animation-delay: 0.18s;
}
.eq.is-on i:nth-child(3) {
  animation-delay: 0.36s;
}
.eq.is-on i:nth-child(4) {
  animation-delay: 0.54s;
}

@keyframes eq {
  0%,
  100% {
    height: 5px;
  }
  50% {
    height: 18px;
  }
}

.speed {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.speed__label {
  font-size: 12px;
  color: var(--muted);
  font-weight: 600;
}

.speed select {
  appearance: none;
  background: var(--surface-2);
  color: var(--text);
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  padding: 6px 26px 6px 10px;
  font-family: inherit;
  font-weight: 600;
  font-size: 13px;
  cursor: pointer;
  background-image: linear-gradient(45deg, transparent 50%, var(--muted) 50%),
    linear-gradient(135deg, var(--muted) 50%, transparent 50%);
  background-position: calc(100% - 14px) 52%, calc(100% - 9px) 52%;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
}

.speed select:hover {
  border-color: var(--line-2);
}

.speed select:focus-visible {
  outline: 2px solid var(--accent-2);
  outline-offset: 1px;
}

/* ---------------- mini queue ---------------- */
.queue {
  margin-top: 28px;
}

.queue__head {
  font-family: var(--display);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 14px;
}

.queue__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.qitem {
  display: flex;
  align-items: center;
  gap: 14px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  padding: 12px 14px;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.qitem:hover {
  border-color: var(--line-2);
  background: var(--surface-2);
}

.qitem.is-active {
  border-color: rgba(29, 185, 84, 0.45);
  background: rgba(29, 185, 84, 0.06);
}

.qitem__play {
  width: 38px;
  height: 38px;
  flex: none;
  border-radius: var(--r-sm);
  border: none;
  cursor: pointer;
  display: grid;
  place-items: center;
  color: var(--text);
  position: relative;
  overflow: hidden;
}

.qitem__play[aria-pressed="true"] {
  color: #03130a;
}

.qitem__play .pause {
  display: none;
}

.qitem__play[aria-pressed="true"] .play {
  display: none;
}

.qitem__play[aria-pressed="true"] .pause {
  display: block;
}

.qitem__main {
  min-width: 0;
  flex: 1;
}

.qitem__name {
  font-weight: 600;
  font-size: 14px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.qitem__artist {
  color: var(--muted);
  font-size: 12.5px;
}

/* compact waveform inside queue item */
.qwave {
  flex: 1 1 90px;
  min-width: 70px;
  max-width: 200px;
  height: 30px;
  display: flex;
  align-items: center;
  gap: 1.5px;
  cursor: pointer;
}

.qwave .bar {
  min-width: 1.5px;
}

.qitem__dur {
  font-variant-numeric: tabular-nums;
  color: var(--muted);
  font-size: 12.5px;
  font-weight: 600;
  flex: none;
}

/* ---------------- toast ---------------- */
.toast {
  position: fixed;
  left: 50%;
  bottom: 26px;
  transform: translateX(-50%) translateY(20px);
  background: var(--surface-2);
  color: var(--text);
  border: 1px solid var(--line-2);
  border-radius: var(--r-full);
  padding: 10px 18px;
  font-size: 13px;
  font-weight: 600;
  box-shadow: var(--shadow);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease, transform 0.25s ease;
  z-index: 50;
}

.toast.is-shown {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ---------------- responsive ---------------- */
@media (max-width: 520px) {
  body {
    padding: 14px;
  }

  .player__top {
    gap: 12px;
  }

  .cover {
    width: 64px;
    height: 64px;
  }

  .meta__stats {
    gap: 10px;
  }

  .controls {
    gap: 10px;
  }

  .controls__speed {
    margin-left: 0;
    width: 100%;
    justify-content: space-between;
  }

  .speed__label {
    display: none;
  }

  .scrub {
    height: 70px;
  }

  .qwave {
    display: none;
  }
}

/* ============================================================
   Music — Waveform / Progress Scrubber
   Vanilla JS, no audio. Playback is simulated with timers.
   ============================================================ */
(function () {
  "use strict";

  /* ---------- helpers ---------- */
  function fmt(sec) {
    sec = Math.max(0, Math.floor(sec));
    var m = Math.floor(sec / 60);
    var s = sec % 60;
    return m + ":" + (s < 10 ? "0" : "") + s;
  }

  function clamp(n, lo, hi) {
    return Math.min(hi, Math.max(lo, n));
  }

  /* Deterministic pseudo-random bar pattern from a seed (mulberry32). */
  function makeBars(seed, count) {
    var t = seed >>> 0;
    function rnd() {
      t += 0x6d2b79f5;
      var x = t;
      x = Math.imul(x ^ (x >>> 15), x | 1);
      x ^= x + Math.imul(x ^ (x >>> 7), x | 61);
      return ((x ^ (x >>> 14)) >>> 0) / 4294967296;
    }
    var out = [];
    for (var i = 0; i < count; i++) {
      // blend a slow sine envelope with noise so it looks like a real waveform
      var env = 0.45 + 0.4 * Math.sin((i / count) * Math.PI * 3.2 + seed);
      var h = clamp(Math.abs(env) * 0.7 + rnd() * 0.45, 0.12, 1);
      out.push(h);
    }
    return out;
  }

  /* toast helper */
  var toastEl = document.getElementById("toast");
  var toastTimer;
  function toast(msg) {
    if (!toastEl) return;
    toastEl.textContent = msg;
    toastEl.classList.add("is-shown");
    clearTimeout(toastTimer);
    toastTimer = setTimeout(function () {
      toastEl.classList.remove("is-shown");
    }, 1800);
  }

  /* ============================================================
     Reusable Waveform Scrubber controller
     ============================================================ */
  function Scrubber(opts) {
    var self = this;
    this.root = opts.root;
    this.barsEl = opts.barsEl;
    this.headEl = opts.headEl || null;
    this.hoverEl = opts.hoverEl || null;
    this.tipEl = opts.tipEl || null;
    this.duration = opts.duration;
    this.barCount = opts.barCount;
    this.onSeek = opts.onSeek || function () {};
    this.bars = [];
    this.progress = 0; // 0..1

    var heights = makeBars(opts.seed, this.barCount);
    var frag = document.createDocumentFragment();
    heights.forEach(function (h) {
      var b = document.createElement("span");
      b.className = "bar";
      b.style.height = Math.round(h * 100) + "%";
      frag.appendChild(b);
      self.bars.push(b);
    });
    this.barsEl.appendChild(frag);

    /* ---- pointer geometry ---- */
    function ratioFromEvent(e) {
      var rect = self.root.getBoundingClientRect();
      var x = (e.touches ? e.touches[0].clientX : e.clientX) - rect.left;
      return clamp(x / rect.width, 0, 1);
    }

    this.dragging = false;

    function down(e) {
      self.dragging = true;
      self.root.classList.add("is-dragging");
      apply(ratioFromEvent(e), true);
      window.addEventListener("pointermove", move);
      window.addEventListener("pointerup", up);
      e.preventDefault();
    }
    function move(e) {
      if (!self.dragging) return;
      apply(ratioFromEvent(e), true);
    }
    function up() {
      self.dragging = false;
      self.root.classList.remove("is-dragging");
      window.removeEventListener("pointermove", move);
      window.removeEventListener("pointerup", up);
    }
    function apply(ratio, fromUser) {
      self.set(ratio);
      if (fromUser) self.onSeek(ratio * self.duration);
    }

    /* ---- hover preview ---- */
    this.root.addEventListener("pointermove", function (e) {
      if (e.pointerType === "touch") return;
      var r = ratioFromEvent(e);
      self.root.classList.add("is-hovering");
      if (self.hoverEl) self.hoverEl.style.left = r * 100 + "%";
      if (self.tipEl) {
        self.tipEl.style.left = r * 100 + "%";
        self.tipEl.textContent = fmt(r * self.duration);
      }
    });
    this.root.addEventListener("pointerleave", function () {
      self.root.classList.remove("is-hovering");
    });

    this.root.addEventListener("pointerdown", down);

    /* ---- keyboard (role=slider) ---- */
    this.root.addEventListener("keydown", function (e) {
      var step = e.shiftKey ? 0.1 : 0.02;
      var r = self.progress;
      if (e.key === "ArrowRight" || e.key === "ArrowUp") r += step;
      else if (e.key === "ArrowLeft" || e.key === "ArrowDown") r -= step;
      else if (e.key === "Home") r = 0;
      else if (e.key === "End") r = 1;
      else return;
      e.preventDefault();
      r = clamp(r, 0, 1);
      self.set(r);
      self.onSeek(r * self.duration);
    });

    this.set(0);
  }

  Scrubber.prototype.set = function (ratio) {
    this.progress = clamp(ratio, 0, 1);
    var cursorIdx = Math.round(this.progress * (this.bars.length - 1));
    for (var i = 0; i < this.bars.length; i++) {
      var played = i / (this.bars.length - 1) <= this.progress;
      this.bars[i].classList.toggle("is-played", played);
      this.bars[i].classList.toggle("is-cursor", i === cursorIdx && this.progress > 0 && this.progress < 1);
    }
    if (this.headEl) this.headEl.style.left = this.progress * 100 + "%";

    if (this.root.getAttribute("role") === "slider") {
      var pct = Math.round(this.progress * 100);
      this.root.setAttribute("aria-valuenow", String(pct));
      this.root.setAttribute(
        "aria-valuetext",
        fmt(this.progress * this.duration) + " of " + fmt(this.duration)
      );
    }
  };

  /* ============================================================
     Primary player — simulated playback engine
     ============================================================ */
  var PRIMARY_DURATION = 222; // 3:42

  var scrub = new Scrubber({
    root: document.getElementById("scrub"),
    barsEl: document.getElementById("scrubBars"),
    headEl: document.getElementById("scrubHead"),
    hoverEl: document.getElementById("scrubHover"),
    tipEl: document.getElementById("scrubTip"),
    duration: PRIMARY_DURATION,
    barCount: 96,
    seed: 1337,
    onSeek: function (sec) {
      player.current = sec;
      player.render();
    }
  });

  var player = {
    current: 0,
    duration: PRIMARY_DURATION,
    playing: false,
    speed: 1,
    raf: null,
    last: 0,

    render: function () {
      curTime.textContent = fmt(this.current);
      if (!scrub.dragging) scrub.set(this.current / this.duration);
    },

    tick: function (ts) {
      if (!this.playing) return;
      if (!this.last) this.last = ts;
      var dt = (ts - this.last) / 1000;
      this.last = ts;
      this.current += dt * this.speed;
      if (this.current >= this.duration) {
        this.current = this.duration;
        this.render();
        this.pause();
        toast("Track finished");
        // auto-reset shortly after, like a real player ending
        return;
      }
      this.render();
      this.raf = requestAnimationFrame(this.tick.bind(this));
    },

    play: function () {
      if (this.current >= this.duration) this.current = 0;
      this.playing = true;
      this.last = 0;
      playBtn.setAttribute("aria-pressed", "true");
      playBtn.setAttribute("aria-label", "Pause");
      eq.classList.add("is-on");
      this.raf = requestAnimationFrame(this.tick.bind(this));
      // pause any queue item that was acting as the active source
      stopAllQueue();
    },

    pause: function () {
      this.playing = false;
      cancelAnimationFrame(this.raf);
      playBtn.setAttribute("aria-pressed", "false");
      playBtn.setAttribute("aria-label", "Play");
      eq.classList.remove("is-on");
    },

    toggle: function () {
      this.playing ? this.pause() : this.play();
    },

    seekBy: function (delta) {
      this.current = clamp(this.current + delta, 0, this.duration);
      this.render();
    }
  };

  var playBtn = document.getElementById("play");
  var curTime = document.getElementById("curTime");
  var totTime = document.getElementById("totTime");
  var eq = document.getElementById("eq");

  totTime.textContent = fmt(PRIMARY_DURATION);

  playBtn.addEventListener("click", function () {
    player.toggle();
  });
  document.getElementById("rewind").addEventListener("click", function () {
    player.seekBy(-10);
    toast("◀ 10s");
  });
  document.getElementById("forward").addEventListener("click", function () {
    player.seekBy(10);
    toast("10s ▶");
  });

  document.getElementById("speed").addEventListener("change", function (e) {
    player.speed = parseFloat(e.target.value);
    toast("Speed " + e.target.value + "×");
  });

  /* like toggle */
  var likeBtn = document.querySelector(".like");
  likeBtn.addEventListener("click", function () {
    var on = likeBtn.getAttribute("aria-pressed") === "true";
    likeBtn.setAttribute("aria-pressed", String(!on));
    toast(on ? "Removed from Liked" : "Added to Liked Songs");
  });

  player.render();

  /* ============================================================
     Mini queue — each row has its own compact scrubber
     ============================================================ */
  var TRACKS = [
    { name: "Paper Lanterns", artist: "Velvet Static", dur: 198, seed: 21, theme: "#8b5cf6" },
    { name: "Glass Harbor", artist: "Neon Tides", dur: 245, seed: 88, theme: "#1db954" },
    { name: "Cobalt Hour", artist: "Halcyon Drift", dur: 176, seed: 305, theme: "#ff3d71" },
    { name: "Slow Static", artist: "Velvet Static", dur: 212, seed: 412, theme: "#38bdf8" }
  ];

  var queueEl = document.getElementById("queue");
  var queueControllers = [];

  function stopAllQueue() {
    queueControllers.forEach(function (c) {
      if (c.playing) c.stop();
    });
  }

  TRACKS.forEach(function (track, idx) {
    var li = document.createElement("li");
    li.className = "qitem";

    var btn = document.createElement("button");
    btn.className = "qitem__play";
    btn.type = "button";
    btn.setAttribute("aria-pressed", "false");
    btn.setAttribute("aria-label", "Play " + track.name);
    btn.style.background = track.theme;
    btn.innerHTML =
      '<svg class="play ico" viewBox="0 0 24 24"><path d="M8 5v14l11-7z"/></svg>' +
      '<svg class="pause ico" viewBox="0 0 24 24"><path d="M7 5h3v14H7zM14 5h3v14h-3z"/></svg>';

    var main = document.createElement("div");
    main.className = "qitem__main";
    main.innerHTML =
      '<div class="qitem__name">' + track.name + "</div>" +
      '<div class="qitem__artist">' + track.artist + "</div>";

    var wave = document.createElement("div");
    wave.className = "qwave";
    wave.setAttribute("role", "slider");
    wave.setAttribute("tabindex", "0");
    wave.setAttribute("aria-label", "Seek " + track.name);
    wave.setAttribute("aria-valuemin", "0");
    wave.setAttribute("aria-valuemax", "100");
    wave.setAttribute("aria-valuenow", "0");

    var dur = document.createElement("span");
    dur.className = "qitem__dur";
    dur.textContent = fmt(track.dur);

    li.appendChild(btn);
    li.appendChild(main);
    li.appendChild(wave);
    li.appendChild(dur);
    queueEl.appendChild(li);

    var ctrl = {
      playing: false,
      current: 0,
      timer: null,
      scrub: null,
      stop: function () {
        this.playing = false;
        clearInterval(this.timer);
        btn.setAttribute("aria-pressed", "false");
        li.classList.remove("is-active");
      },
      start: function () {
        // exclusive playback: stop primary + other queue items
        player.pause();
        stopAllQueue();
        this.playing = true;
        if (this.current >= track.dur) this.current = 0;
        btn.setAttribute("aria-pressed", "true");
        li.classList.add("is-active");
        var c = this;
        this.timer = setInterval(function () {
          c.current += 0.25;
          if (c.current >= track.dur) {
            c.current = track.dur;
            c.scrub.set(1);
            dur.textContent = fmt(track.dur);
            c.stop();
            return;
          }
          c.scrub.set(c.current / track.dur);
          dur.textContent = fmt(track.dur - c.current);
        }, 100);
      }
    };

    ctrl.scrub = new Scrubber({
      root: wave,
      barsEl: wave,
      duration: track.dur,
      barCount: 48,
      seed: track.seed,
      onSeek: function (sec) {
        ctrl.current = sec;
        dur.textContent = fmt(track.dur - sec);
      }
    });

    btn.addEventListener("click", function () {
      if (ctrl.playing) {
        ctrl.stop();
      } else {
        ctrl.start();
        toast("Playing · " + track.name);
      }
    });

    queueControllers.push(ctrl);
  });
})();

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1" />
  <title>Music — Waveform / Progress Scrubber</title>
  <link rel="preconnect" href="https://fonts.googleapis.com" />
  <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
  <link
    href="https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@500;600;700&family=Inter:wght@400;500;600;700;800&display=swap"
    rel="stylesheet"
  />
  <link rel="stylesheet" href="style.css" />
</head>
<body>
  <main class="stage">
    <header class="stage__head">
      <span class="kicker">Now Playing</span>
      <h1 class="stage__title">Waveform Scrubber</h1>
      <p class="stage__sub">A SoundCloud-style progress scrubber with draggable playhead, hover preview, and variable playback speed.</p>
    </header>

    <!-- ============ PRIMARY PLAYER ============ -->
    <section class="player" aria-label="Now playing track">
      <div class="player__top">
        <div class="cover" data-theme="reservoir" aria-hidden="true">
          <span class="cover__shape cover__shape--1"></span>
          <span class="cover__shape cover__shape--2"></span>
          <span class="cover__ring"></span>
        </div>
        <div class="meta">
          <span class="meta__badge">Single · Lossless</span>
          <h2 class="meta__title">Midnight Reservoir</h2>
          <p class="meta__artist">Neon Tides</p>
          <div class="meta__stats">
            <span class="stat"><svg viewBox="0 0 24 24" class="ico"><path d="M8 5v14l11-7z"/></svg> 1,284,902 plays</span>
            <span class="stat"><svg viewBox="0 0 24 24" class="ico"><path d="M12 21s-7.5-4.6-10-9.2C.7 9.1 1.6 5.7 4.6 4.7 7 3.9 9 5.1 12 8c3-2.9 5-4.1 7.4-3.3 3 .9 3.9 4.4 2.6 7.1C19.5 16.4 12 21 12 21z"/></svg> 42.1k</span>
          </div>
        </div>
        <button class="like" type="button" aria-pressed="false" aria-label="Like this track">
          <svg viewBox="0 0 24 24" class="ico"><path d="M12 21s-7.5-4.6-10-9.2C.7 9.1 1.6 5.7 4.6 4.7 7 3.9 9 5.1 12 8c3-2.9 5-4.1 7.4-3.3 3 .9 3.9 4.4 2.6 7.1C19.5 16.4 12 21 12 21z"/></svg>
        </button>
      </div>

      <!-- The scrubber: tooltip + hover preview + bars are injected by JS -->
      <div
        class="scrub"
        id="scrub"
        role="slider"
        tabindex="0"
        aria-label="Seek through track"
        aria-valuemin="0"
        aria-valuemax="100"
        aria-valuenow="0"
        aria-valuetext="0:00 of 3:42"
      >
        <div class="scrub__hover" id="scrubHover" aria-hidden="true"></div>
        <div class="scrub__tip" id="scrubTip" aria-hidden="true">0:00</div>
        <div class="scrub__bars" id="scrubBars"></div>
        <div class="scrub__head" id="scrubHead" aria-hidden="true"></div>
      </div>

      <div class="controls">
        <div class="controls__left">
          <button class="iconbtn" id="rewind" type="button" aria-label="Rewind 10 seconds">
            <svg viewBox="0 0 24 24" class="ico"><path d="M12 5V1L7 6l5 5V7a5 5 0 1 1-5 5H5a7 7 0 1 0 7-7z"/></svg>
          </button>
          <button class="playbtn" id="play" type="button" aria-pressed="false" aria-label="Play">
            <svg class="playbtn__icon" viewBox="0 0 24 24" aria-hidden="true">
              <path class="playbtn__play" d="M8 5v14l11-7z"/>
              <path class="playbtn__pause" d="M7 5h3v14H7zM14 5h3v14h-3z"/>
            </svg>
          </button>
          <button class="iconbtn" id="forward" type="button" aria-label="Forward 10 seconds">
            <svg viewBox="0 0 24 24" class="ico"><path d="M12 5V1l5 5-5 5V7a5 5 0 1 0 5 5h2a7 7 0 1 1-7-7z"/></svg>
          </button>
        </div>

        <div class="controls__time">
          <span class="time time--current" id="curTime">0:00</span>
          <span class="time__sep">/</span>
          <span class="time time--total" id="totTime">3:42</span>
        </div>

        <div class="controls__speed">
          <span class="eq" id="eq" aria-hidden="true"><i></i><i></i><i></i><i></i></span>
          <label class="speed">
            <span class="speed__label">Speed</span>
            <select id="speed" aria-label="Playback speed">
              <option value="0.5">0.5×</option>
              <option value="0.75">0.75×</option>
              <option value="1" selected>1×</option>
              <option value="1.25">1.25×</option>
              <option value="1.5">1.5×</option>
              <option value="2">2×</option>
            </select>
          </label>
        </div>
      </div>
    </section>

    <!-- ============ MINI QUEUE — compact scrubbers ============ -->
    <section class="queue" aria-label="Up next">
      <h3 class="queue__head">Up next in the queue</h3>
      <ul class="queue__list" id="queue"></ul>
    </section>

    <div class="toast" id="toast" role="status" aria-live="polite"></div>
  </main>

  <script src="script.js"></script>
</body>
</html>