* { box-sizing: border-box; }

:root {
  --void: #07090c;
  --panel: rgba(18, 24, 32, 0.72);
  --line: rgba(255, 200, 120, 0.14);
  --amber: #ffb347;
  --amber-dim: rgba(255, 179, 71, 0.55);
  --teal: #3dd6c6;
  --ink: rgba(255, 248, 235, 0.92);
  --ink-dim: rgba(255, 248, 235, 0.42);
  --key-white: rgba(255, 248, 235, 0.92);
  --key-black: #141a22;
}

html, body { height: 100%; }

body {
  margin: 0;
  color: var(--ink);
  font-family: "DM Serif Display", Georgia, serif;
  background:
    radial-gradient(ellipse 80% 50% at 50% -10%, rgba(255, 179, 71, 0.16), transparent 55%),
    radial-gradient(circle at 85% 90%, rgba(61, 214, 198, 0.08), transparent 40%),
    var(--void);
  overflow-x: hidden;
}

main {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  gap: 22px;
  padding: clamp(22px, 4vw, 52px);
  max-width: 1280px;
  margin: 0 auto;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 20px;
  flex-wrap: wrap;
}

.eyebrow {
  font-family: "IBM Plex Mono", monospace;
  color: var(--amber-dim);
  font-size: 11px;
  letter-spacing: 0.32em;
  text-transform: uppercase;
}

h1 {
  margin: 8px 0 0;
  font-size: clamp(36px, 6.5vw, 76px);
  line-height: 0.98;
  letter-spacing: -0.02em;
  font-weight: 400;
}

h1 em { font-style: italic; color: var(--amber); }

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

.btn {
  border: 1px solid var(--line);
  background: rgba(255, 179, 71, 0.08);
  color: var(--ink);
  padding: 10px 16px;
  border-radius: 999px;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  cursor: pointer;
}

.btn[data-on] {
  border-color: rgba(255, 179, 71, 0.5);
  background: rgba(255, 179, 71, 0.18);
  color: var(--amber);
}

.btn.ghost { background: transparent; color: var(--ink-dim); }

/* ── Pitch antenna + readout ─────────────────────────────────────────────── */

.stage {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 20px;
  align-items: stretch;
  min-height: 300px;
}

.antenna {
  position: relative;
  border: 1px solid var(--line);
  border-radius: 28px;
  background: var(--panel);
  overflow: hidden;
  display: flex;
  align-items: stretch;
  justify-content: center;
  padding: 28px 40px;
}

.antenna .badge {
  position: absolute;
  top: 18px;
  left: 22px;
  font-family: "IBM Plex Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--ink-dim);
}

.pitch-ladder {
  position: relative;
  width: min(120px, 22vw);
  height: 100%;
  min-height: 220px;
  border-radius: 999px;
  background: rgba(0, 0, 0, 0.35);
  border: 1px solid var(--line);
  overflow: hidden;
}

.pitch-ladder::before {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    to top,
    transparent 0px,
    transparent 11.1%,
    rgba(255, 179, 71, 0.12) 11.1%,
    rgba(255, 179, 71, 0.12) calc(11.1% + 1px)
  );
}

.pitch-dot {
  position: absolute;
  left: 50%;
  width: 18px;
  height: 18px;
  margin-left: -9px;
  border-radius: 999px;
  background: var(--amber);
  box-shadow: 0 0 24px rgba(255, 179, 71, 0.65);
  transform: translateY(-50%);
  transition: top 0.06s ease-out;
}

.pitch-glow {
  position: absolute;
  left: 50%;
  bottom: 0;
  width: 140%;
  margin-left: -70%;
  height: 40%;
  background: radial-gradient(ellipse at center bottom, rgba(255, 179, 71, 0.25), transparent 70%);
  pointer-events: none;
  transition: height 0.08s ease-out, opacity 0.08s ease-out;
}

.readout { display: flex; flex-direction: column; gap: 14px; }

.hz-card {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 24px 28px;
  border-radius: 24px;
  background: var(--panel);
  border: 1px solid var(--line);
}

.hz-card .label {
  font-family: "IBM Plex Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--ink-dim);
}

.hz-card .val {
  margin-top: 8px;
  font-size: clamp(48px, 6.5vw, 80px);
  font-variant-numeric: tabular-nums;
  line-height: 1;
  color: var(--amber);
}

.hz-card .val span {
  font-size: clamp(16px, 2vw, 22px);
  color: var(--ink-dim);
  margin-left: 6px;
}

.note {
  font-family: "IBM Plex Mono", monospace;
  font-size: 13px;
  color: var(--teal);
  letter-spacing: 0.08em;
  margin-top: 8px;
}

.source-tag {
  font-family: "IBM Plex Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-dim);
  margin-top: 6px;
}

.source-tag[data-src="pot"] { color: var(--amber-dim); }
.source-tag[data-src="key"] { color: var(--teal); }

.card {
  border-radius: 20px;
  background: rgba(0, 0, 0, 0.35);
  border: 1px solid var(--line);
  padding: 16px 18px;
}

.card .label {
  font-family: "IBM Plex Mono", monospace;
  font-size: 10px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--ink-dim);
  margin-bottom: 10px;
}

.card gr-slider { width: 100%; padding: 0; border: none; background: none; }
.card gr-gauge { width: 100%; }

/* ── Performance keyboard ────────────────────────────────────────────────── */

.keyboard-panel {
  border: 1px solid var(--line);
  border-radius: 24px;
  background: var(--panel);
  padding: 20px 22px 18px;
}

.keyboard-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 14px;
}

.keyboard-head h2 {
  margin: 0;
  font-size: 22px;
  font-weight: 400;
  letter-spacing: -0.01em;
}

.keyboard-head p {
  margin: 0;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  color: var(--ink-dim);
  line-height: 1.6;
}

.octave-row {
  display: flex;
  gap: 8px;
  margin-bottom: 14px;
}

.octave-row .btn { padding: 8px 14px; font-size: 10px; }

.octave-label {
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  color: var(--amber);
  align-self: center;
  margin-left: 6px;
}

.piano-wrap {
  position: relative;
  overflow-x: auto;
  padding-bottom: 4px;
}

.piano {
  position: relative;
  display: flex;
  gap: 3px;
  min-width: min(100%, 720px);
  height: 148px;
  user-select: none;
}

.pot-marker {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 3px;
  margin-left: -1.5px;
  background: var(--amber);
  box-shadow: 0 0 12px rgba(255, 179, 71, 0.8);
  border-radius: 999px;
  pointer-events: none;
  z-index: 3;
  transition: left 0.05s linear;
}

.key {
  position: relative;
  border: none;
  cursor: pointer;
  border-radius: 0 0 8px 8px;
  font-family: "IBM Plex Mono", monospace;
  font-size: 9px;
  letter-spacing: 0.06em;
  transition: background 0.05s, transform 0.05s;
}

.key.white {
  flex: 1;
  min-width: 36px;
  background: var(--key-white);
  color: #1a1410;
  z-index: 1;
  padding-bottom: 8px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  align-items: center;
  gap: 2px;
}

.key.black {
  position: absolute;
  width: calc(100% / 14 * 0.62);
  min-width: 22px;
  max-width: 34px;
  height: 58%;
  top: 0;
  background: var(--key-black);
  color: rgba(255, 248, 235, 0.55);
  z-index: 2;
  border: 1px solid rgba(255, 179, 71, 0.2);
  border-radius: 0 0 6px 6px;
  padding-bottom: 6px;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  align-items: center;
}

.key .bind { opacity: 0.45; font-size: 8px; }

.key.active, .key[data-down] {
  background: var(--amber);
  color: #1a1410;
  transform: translateY(2px);
}

.key.black.active, .key.black[data-down] {
  background: #c9872e;
  color: #fff;
}

.key.near { box-shadow: inset 0 -3px 0 var(--teal); }

/* ── Footer ──────────────────────────────────────────────────────────────── */

.foot {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 20px;
  align-items: start;
}

.hint {
  font-family: "IBM Plex Mono", monospace;
  font-size: 12px;
  color: var(--ink-dim);
  line-height: 1.75;
  margin: 0;
}

.hint code { color: var(--amber-dim); }

.hint kbd {
  font-family: inherit;
  background: rgba(255, 179, 71, 0.12);
  padding: 1px 5px;
  border-radius: 4px;
  border: 1px solid var(--line);
}

@media (max-width: 860px) {
  .stage, .foot { grid-template-columns: 1fr; }
  .piano { height: 128px; }
}