:root {
  --bg: #f5f4ef;
  --panel: #fffef9;
  --ink: #1d1d1d;
  --muted: #5a5a5a;
  --accent: #f4a100;
  --accent-dark: #b87000;
  --key-white: #fff;
  --key-white-off: #ece8de;
  --key-black: #2b2b2b;
  --key-black-off: #515151;
  --border: #d5d0c4;
  --field-bg: #ffffff;
  --field-border: #bbbbbb;
  --gradient-a: #fff9dd;
  --gradient-b: #ece5d7;
}

:root[data-theme="dark"] {
  --bg: #12131a;
  --panel: #1b1d25;
  --ink: #eceef5;
  --muted: #aeb4c4;
  --accent: #f0a93d;
  --accent-dark: #b87715;
  --key-white: #dedde3;
  --key-white-off: #b6b5be;
  --key-black: #121218;
  --key-black-off: #2e2f39;
  --border: #303445;
  --field-bg: #202330;
  --field-border: #464d63;
  --gradient-a: #1a1f2f;
  --gradient-b: #0f1119;
}

:root[data-theme="studio"] {
  --bg: #142425;
  --panel: #1d3132;
  --ink: #eff9f2;
  --muted: #a9c8bb;
  --accent: #f5b14c;
  --accent-dark: #b5771d;
  --key-white: #ebf2ec;
  --key-white-off: #b9c7bc;
  --key-black: #0e1b1b;
  --key-black-off: #2f4643;
  --border: #395a56;
  --field-bg: #264141;
  --field-border: #4f7670;
  --gradient-a: #315e5d;
  --gradient-b: #102122;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Trebuchet MS", "Segoe UI", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at 5% 10%, var(--gradient-a) 0%, transparent 35%),
    radial-gradient(circle at 95% 0%, var(--gradient-b) 0%, transparent 33%),
    var(--bg);
  min-height: 100vh;
}

.app {
  max-width: 1100px;
  margin: 0 auto;
  padding: 1.5rem 1rem 2.5rem;
}

.header-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
}

.header h1 {
  margin: 0;
  font-size: clamp(1.5rem, 2.5vw, 2.2rem);
}

.theme-control {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  min-width: 140px;
  font-size: 0.8rem;
  font-weight: 700;
}

.theme-control select {
  margin-top: 0.2rem;
}

.header p {
  margin: 0.4rem 0 1.2rem;
  color: var(--muted);
}

.controls {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 0.8rem;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.9rem;
}

label,
legend {
  font-size: 0.95rem;
  font-weight: 600;
}

select {
  margin-top: 0.35rem;
  width: 100%;
  padding: 0.55rem;
  border-radius: 8px;
  border: 1px solid var(--field-border);
  font-size: 0.96rem;
  background: var(--field-bg);
  color: var(--ink);
}

.toggles {
  margin: 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  display: grid;
  gap: 0.35rem;
  padding: 0.6rem;
}

.actions {
  display: flex;
  flex-direction: column;
}

.actions-label {
  font-size: 0.95rem;
  font-weight: 600;
}

#play-scale-btn {
  margin-top: 0.35rem;
  width: 100%;
  padding: 0.62rem 0.75rem;
  border-radius: 8px;
  border: 1px solid color-mix(in srgb, var(--accent-dark) 70%, #000 30%);
  background: linear-gradient(180deg, var(--accent) 0%, var(--accent-dark) 100%);
  color: #fff;
  font-size: 0.95rem;
  font-weight: 700;
  cursor: pointer;
  transition: transform 80ms ease, filter 120ms ease;
}

#play-scale-btn:hover {
  transform: translateY(-1px);
  filter: brightness(1.04);
}

#play-scale-btn:active {
  transform: translateY(1px);
}

#play-scale-btn:disabled {
  opacity: 0.65;
  cursor: default;
  transform: none;
  filter: none;
}

.toggles label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 500;
}

.scale-meta {
  margin: 0.8rem 0;
  color: var(--muted);
}

.scale-meta p {
  margin: 0.3rem 0;
}

.piano-roll {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.5rem;
  background: color-mix(in srgb, var(--panel) 55%, #7e7664 45%);
  overflow-x: auto;
}

.keyboard-track {
  --white-key-width: 48px;
  --black-key-width: 30px;
  position: relative;
  min-width: 100%;
  width: calc(var(--white-key-width) * var(--key-span, 15));
  height: 190px;
}

.key {
  position: absolute;
  top: 0;
  width: var(--white-key-width);
  height: 100%;
  border: 1px solid rgba(0, 0, 0, 0.25);
  border-radius: 6px;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  align-items: center;
  padding: 0.35rem 0.2rem;
  transition: transform 80ms ease, box-shadow 120ms ease, filter 120ms ease;
  user-select: none;
}

.key:hover {
  transform: translateY(-1px);
}

.key:disabled {
  cursor: default;
}

.key:disabled:hover {
  transform: none;
}

.key:active,
.key.playing {
  transform: translateY(1px);
  box-shadow: inset 0 0 0 3px rgba(255, 255, 255, 0.9), 0 0 14px rgba(255, 190, 70, 0.85);
  filter: brightness(1.18) saturate(1.25);
  z-index: 4;
}

.key.white.playing {
  background: linear-gradient(180deg, #ffe8b7 0%, #ffbd3f 100%);
}

.key.black.playing {
  background: linear-gradient(180deg, #ffc86d 0%, #d07e12 100%);
}

.key.white {
  z-index: 1;
}

.key.white.out {
  background: var(--key-white-off);
}

.key.white.in {
  background: linear-gradient(180deg, #ffe3a8 0%, #ffc756 100%);
}

.key.black {
  width: var(--black-key-width);
  height: 62%;
  z-index: 2;
  border-radius: 0 0 5px 5px;
}

.key.black.out {
  background: var(--key-black-off);
  color: #f8f8f8;
}

.key.black.in {
  background: linear-gradient(180deg, #ffb347 0%, var(--accent-dark) 100%);
  color: #fff;
}

.key-note,
.key-degree {
  font-size: 0.78rem;
  line-height: 1.2;
  text-shadow: 0 1px 1px rgba(0, 0, 0, 0.22);
}

.key.white .key-note,
.key.white .key-degree {
  text-shadow: none;
}

.key.black .key-note {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  transform: rotate(180deg);
  line-height: 1;
  letter-spacing: 0.03em;
}

.hint {
  margin-top: 0.55rem;
  font-size: 0.88rem;
  color: var(--muted);
}

@media (max-width: 680px) {
  .header-top {
    align-items: stretch;
  }

  .theme-control {
    align-items: stretch;
  }

  .keyboard-track {
    --white-key-width: 38px;
    --black-key-width: 24px;
    height: 150px;
  }

  .piano-roll {
    padding: 0.4rem;
  }
}