:root {
  color-scheme: dark;

  --background: #0b0d10;
  --surface: #111419;
  --surface-raised: #171b21;
  --line: rgba(255, 255, 255, 0.1);
  --muted: #8d96a3;
  --text: #f4f6f8;
  --accent: #9ae6b4;
  --accent-soft: rgba(154, 230, 180, 0.1);
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
  margin: 0;
}

body {
  min-height: 100vh;

  background: var(--background);
  color: var(--text);

  font-family:
    Inter,
    ui-sans-serif,
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    sans-serif;
}

button,
select,
input {
  font: inherit;
}

.app {
  min-height: 100vh;

  display: grid;
  grid-template-rows: auto auto auto minmax(0, 1fr);
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 20px clamp(20px, 4vw, 56px);
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: var(--text);
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
}

.brand-mark {
  width: 10px;
  height: 10px;
  background: linear-gradient(135deg, #67e8f9, var(--accent));
  border-radius: 50%;
  box-shadow: 0 0 14px rgba(154, 230, 180, 0.4);
}

.site-header > p {
  margin: 0;
  color: var(--muted);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}

.toolbar {
  display: flex;
  align-items: end;
  justify-content: space-between;

  gap: 32px;

  padding: 28px 32px 24px;

  border-bottom: 1px solid var(--line);
}

.eyebrow,
.summary-label {
  margin: 0 0 6px;

  color: var(--muted);

  font-size: 11px;
  font-weight: 700;

  letter-spacing: 0.16em;
  text-transform: uppercase;
}

h1,
h2,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 0;

  font-size: clamp(25px, 3vw, 38px);
  font-weight: 620;

  letter-spacing: -0.04em;
}

.selectors {
  display: flex;
  align-items: end;

  gap: 12px;
}

.root-control,
.type-control {
  min-width: 150px;
}

.root-control > span,
.type-control legend {
  display: block;

  margin-bottom: 7px;

  color: var(--muted);

  font-size: 11px;
  font-weight: 700;

  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.root-control select {
  width: 100%;
  height: 42px;

  padding: 0 38px 0 13px;

  appearance: none;

  background:
    linear-gradient(45deg, transparent 50%, var(--muted) 50%)
      calc(100% - 17px) 18px / 5px 5px no-repeat,
    linear-gradient(135deg, var(--muted) 50%, transparent 50%)
      calc(100% - 12px) 18px / 5px 5px no-repeat,
    var(--surface-raised);
  color: var(--text);

  border: 1px solid var(--line);
  border-radius: 8px;

  outline: none;
}

.root-control select:focus-visible {
  border-color: var(--accent);
}

.type-control {
  min-width: 265px;

  display: grid;
  grid-template-columns: 1fr 1.35fr;

  margin: 0;
  padding: 0;

  border: 0;
}

.type-control legend {
  grid-column: 1 / -1;
}

.type-control label {
  cursor: pointer;
}

.type-control input {
  position: absolute;

  opacity: 0;
  pointer-events: none;
}

.type-control span {
  height: 42px;

  display: grid;
  place-items: center;

  padding: 0 14px;

  background: var(--surface-raised);
  color: var(--muted);

  border: 1px solid var(--line);
}

.type-control label:first-of-type span {
  border-radius: 8px 0 0 8px;
}

.type-control label:last-of-type span {
  margin-left: -1px;

  border-radius: 0 8px 8px 0;
}

.type-control input:checked + span {
  position: relative;
  z-index: 1;

  background: var(--accent-soft);
  color: var(--accent);

  border-color: rgba(154, 230, 180, 0.55);
}

.type-control input:focus-visible + span {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.summary {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: end;

  gap: 28px;

  padding: 22px 32px;

  border-bottom: 1px solid var(--line);
}

.summary h2 {
  margin-bottom: 0;

  font-size: clamp(22px, 2.3vw, 32px);
  font-weight: 620;

  letter-spacing: -0.03em;
}

.formula,
.related-scale {
  margin-bottom: 2px;

  color: var(--muted);

  font-size: 13px;
  letter-spacing: 0.08em;
}

.related-scale {
  letter-spacing: normal;
}

.summary-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;

  gap: 16px;
}

.play-scale {
  min-width: 112px;
  height: 38px;

  display: inline-flex;
  align-items: center;
  justify-content: center;

  gap: 8px;

  padding: 0 14px;

  background: var(--accent-soft);
  color: var(--accent);

  border: 1px solid rgba(154, 230, 180, 0.38);
  border-radius: 8px;

  cursor: pointer;
}

.play-scale:hover {
  border-color: var(--accent);
}

.play-scale:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.play-scale.playing {
  background: var(--accent);
  color: #102117;
}

.scale-grid {
  min-height: 0;

  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
}

.degree-card {
  min-width: 0;

  display: flex;
  flex-direction: column;
  justify-content: space-between;

  padding: clamp(20px, 2.2vw, 34px);

  border-right: 1px solid var(--line);

  cursor: pointer;

  transition:
    background-color 0.15s ease,
    box-shadow 0.15s ease;
}

.degree-card:hover {
  background-color: rgba(255, 255, 255, 0.025);
}

.degree-card:focus-visible {
  position: relative;
  z-index: 1;

  outline: 2px solid var(--accent);
  outline-offset: -2px;
}

.degree-card:last-child {
  border-right: 0;
}

.degree-card.tonic {
  background:
    linear-gradient(
      180deg,
      var(--accent-soft),
      transparent 72%
    );
}

.degree-card.sounding {
  background-color: var(--accent-soft);

  box-shadow:
    inset 0 3px 0 var(--accent);
}

.degree-number {
  display: flex;
  align-items: center;
  justify-content: space-between;

  gap: 10px;

  color: var(--muted);

  font-size: 12px;
  font-weight: 700;

  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.degree-roman {
  color: var(--accent);
}

.note-name {
  margin: auto 0;

  font-size: clamp(46px, 7vw, 104px);
  font-weight: 540;

  line-height: 0.9;
  letter-spacing: -0.07em;
}

.note-name sup {
  position: relative;
  top: -0.12em;

  margin-left: 2px;

  color: var(--accent);

  font-size: 0.45em;
}

.chord-reference {
  display: flex;
  align-items: baseline;
  justify-content: space-between;

  gap: 10px;

  margin-bottom: clamp(18px, 2vw, 30px);
  padding: 10px 0;

  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.chord-name {
  color: var(--accent);

  font-size: clamp(18px, 1.8vw, 26px);
  font-weight: 650;

  letter-spacing: -0.03em;
}

.chord-name sup {
  font-size: 0.65em;
}

.chord-tones {
  overflow: hidden;

  color: var(--muted);

  font-size: 11px;

  text-align: right;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.degree-meta {
  display: grid;

  gap: 9px;
}

.meta-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;

  gap: 12px;

  padding-top: 9px;

  border-top: 1px solid var(--line);

  font-size: 12px;
}

.meta-label {
  color: var(--muted);
}

.meta-value {
  overflow: hidden;

  font-weight: 600;

  text-align: right;
  text-overflow: ellipsis;
  white-space: nowrap;
}

@media (max-width: 900px) {
  .app {
    display: block;
  }

  .toolbar {
    align-items: stretch;
  }

  .scale-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .degree-card {
    min-height: 320px;

    border-bottom: 1px solid var(--line);
  }

  .degree-card:nth-child(2n) {
    border-right: 0;
  }

  .degree-card:last-child {
    border-right: 1px solid var(--line);
  }

  .note-name {
    font-size: clamp(64px, 15vw, 100px);
  }
}

@media (max-width: 650px) {
  .site-header {
    padding-right: 18px;
    padding-left: 18px;
  }

  .toolbar,
  .selectors {
    flex-direction: column;
  }

  .toolbar {
    align-items: stretch;

    padding: 22px 18px;
  }

  .selectors {
    align-items: stretch;

    gap: 14px;
  }

  .type-control {
    width: 100%;
  }

  .summary {
    grid-template-columns: 1fr;

    gap: 10px;

    padding: 20px 18px;
  }

  .related-scale {
    margin-bottom: 0;
  }

  .summary-actions {
    justify-content: space-between;
  }

  .scale-grid {
    grid-template-columns: 1fr;
  }

  .degree-card,
  .degree-card:nth-child(2n),
  .degree-card:last-child {
    min-height: 280px;

    border-right: 0;
  }
}