:root {
  color-scheme: dark;
  --bg: #101216;
  --surface: #191c22;
  --surface-raised: #21252d;
  --surface-active: #2b313b;
  --border: #363c47;
  --border-strong: #515967;
  --text: #f2f0e9;
  --muted: #a8adb7;
  --accent: #f0b84b;
  --accent-dark: #1f180a;
  --play: #7fc89a;
  --danger: #e48078;
  --focus: #8bc8ff;
  --radius: 8px;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
}

* {
  box-sizing: border-box;
}

html {
  min-width: 320px;
  background: var(--bg);
}

body {
  min-width: 320px;
  min-height: 100vh;
  margin: 0;
  color: var(--text);
  background: var(--bg);
}

button,
input,
select {
  font: inherit;
}

button {
  color: inherit;
}

button,
input,
select {
  min-height: 44px;
}

button:focus-visible,
input:focus-visible,
select:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

.app-header {
  border-bottom: 1px solid var(--border);
  background: #15181d;
}

.header-inner,
.app-layout,
footer {
  width: min(100%, 1440px);
  margin-inline: auto;
}

.header-inner {
  display: grid;
  gap: 18px;
  padding: 20px 16px;
}

.brand-block h1,
.section-heading h2,
.export-row h2 {
  margin: 0;
  letter-spacing: -0.02em;
}

.brand-block h1 {
  font-size: clamp(1.45rem, 7vw, 2rem);
}

.eyebrow {
  margin: 0 0 4px;
  color: var(--accent);
  font: 700 0.7rem/1.2 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  letter-spacing: 0.14em;
}

.field {
  display: grid;
  gap: 6px;
  min-width: 0;
}

.field span,
.keyboard-header > span,
.octave-control > span {
  color: var(--muted);
  font-size: 0.77rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

input,
select {
  width: 100%;
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  padding: 0 11px;
  color: var(--text);
  background: var(--surface);
}

.field-name input {
  font-size: 1rem;
  font-weight: 650;
}

.transport {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.transport-button,
.action-button,
.file-button,
.export-button {
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  padding: 0 16px;
  font-weight: 800;
  cursor: pointer;
  background: var(--surface-raised);
}

.transport-button:hover,
.action-button:hover,
.file-button:hover,
.export-button:hover {
  border-color: #737d8d;
  background: var(--surface-active);
}

.transport-button.play {
  color: var(--play);
}

.transport-button.stop {
  color: var(--danger);
}

.transport-button.is-active {
  border-color: var(--play);
  color: #102017;
  background: var(--play);
}

.transport-status {
  grid-column: 1 / -1;
  min-height: 1rem;
  color: var(--muted);
  font-size: 0.78rem;
  text-align: center;
}

.global-controls {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.global-controls .field:nth-child(3) {
  grid-column: span 2;
}

.app-layout {
  display: grid;
  gap: 16px;
  padding: 16px;
}

.editor-column {
  display: grid;
  min-width: 0;
  gap: 16px;
}

.panel,
.export-row {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}

.panel {
  padding: 16px;
}

.section-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}

.section-heading h2,
.export-row h2 {
  font-size: 1.15rem;
}

.section-hint,
.keyboard-help,
.export-row p,
footer p {
  margin: 0;
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.5;
}

.section-hint {
  display: none;
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 8px;
}

.step-button {
  position: relative;
  display: grid;
  min-width: 0;
  min-height: 76px;
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  padding: 8px 5px 7px;
  overflow: hidden;
  color: var(--text);
  cursor: pointer;
  background: var(--surface-raised);
}

.step-button:hover {
  border-color: #757e8c;
}

.step-button.is-selected {
  border: 2px solid var(--accent);
  padding: 7px 4px 6px;
  box-shadow: inset 0 -4px 0 var(--accent);
}

.step-button.is-playing {
  border-color: var(--play);
  color: #09140d;
  background: var(--play);
  box-shadow: 0 0 0 2px rgb(127 200 154 / 20%);
}

.step-button.is-selected.is-playing {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}

.step-number {
  justify-self: start;
  color: var(--muted);
  font: 700 0.67rem/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.step-button.is-playing .step-number,
.step-button.is-playing .step-legato {
  color: #213b2a;
}

.step-note {
  align-self: center;
  overflow: hidden;
  font: 800 clamp(0.87rem, 4vw, 1.05rem)/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  text-overflow: ellipsis;
}

.step-button.is-rest .step-note {
  color: var(--muted);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
}

.step-button.is-playing.is-rest .step-note {
  color: #213b2a;
}

.step-legato {
  min-height: 0.72rem;
  color: var(--accent);
  font: 800 0.61rem/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  letter-spacing: 0.08em;
}

.selected-heading {
  align-items: center;
}

.selected-value {
  color: var(--accent);
  font: 800 1.1rem/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.step-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 24px;
}

.action-button {
  min-height: 48px;
}

.rest-button.is-active {
  border-color: var(--danger);
  color: #21100e;
  background: var(--danger);
}

.legato-button.is-active {
  border-color: var(--accent);
  color: var(--accent-dark);
  background: var(--accent);
}

.legato-button:disabled {
  opacity: 0.42;
  cursor: not-allowed;
}

.keyboard-header {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
}

.octave-control {
  display: grid;
  justify-items: end;
  gap: 5px;
}

.octave-stepper {
  display: grid;
  grid-template-columns: 44px 48px 44px;
  align-items: center;
  overflow: hidden;
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  background: var(--surface-raised);
}

.octave-button {
  min-height: 42px;
  border: 0;
  padding: 0;
  color: var(--text);
  font-size: 1.35rem;
  font-weight: 800;
  cursor: pointer;
  background: transparent;
}

.octave-button:hover:not(:disabled) {
  background: var(--surface-active);
}

.octave-button:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

#keyboard-octave {
  display: grid;
  place-items: center;
  align-self: stretch;
  border-inline: 1px solid var(--border-strong);
  font: 800 1rem/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.keyboard-header h3 {
  margin: 0;
  font-size: 0.95rem;
}

.piano {
  position: relative;
  display: flex;
  height: 154px;
  margin-bottom: 10px;
  border: 1px solid #050607;
  border-radius: 6px;
  overflow: hidden;
  background: #070809;
}

.piano-key {
  cursor: pointer;
  touch-action: manipulation;
  user-select: none;
}

.piano-key:active,
.piano-key.is-pressed {
  background: var(--accent);
}

.white-key {
  position: relative;
  z-index: 1;
  flex: 1;
  align-items: flex-end;
  justify-content: center;
  min-width: 0;
  height: 100%;
  border: 0;
  border-right: 1px solid #777b82;
  border-radius: 0;
  padding: 0 0 10px;
  color: #17191c;
  background: #e9e7df;
}

.white-key:last-of-type {
  border-right: 0;
}

.white-key span {
  position: absolute;
  bottom: 10px;
  left: 50%;
  translate: -50% 0;
  font-size: 0.74rem;
  font-weight: 800;
}

.black-key {
  position: absolute;
  z-index: 2;
  top: 0;
  width: 12%;
  min-height: 0;
  height: 61%;
  border: 1px solid #050607;
  border-radius: 0 0 4px 4px;
  padding: 0;
  color: #f3f1ea;
  background: #22252b;
  box-shadow: 0 3px 3px rgb(0 0 0 / 42%);
}

.black-key span {
  position: absolute;
  bottom: 8px;
  left: 50%;
  translate: -50% 0;
  font-size: 0.57rem;
  font-weight: 800;
}

.black-cs { left: 8.3%; }
.black-ds { left: 22.6%; }
.black-fs { left: 51.2%; }
.black-gs { left: 65.5%; }
.black-as { left: 79.8%; }

.export-row {
  display: grid;
  gap: 16px;
  padding: 16px;
}

.export-row p {
  margin-top: 4px;
}

.file-actions {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.file-button {
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  padding: 0 14px;
  font-weight: 800;
  cursor: pointer;
  background: var(--surface-raised);
}

.export-button {
  border-color: var(--accent);
  color: var(--accent-dark);
  background: var(--accent);
}

.export-button:hover {
  border-color: #ffd47b;
  background: #ffd078;
}

#file-status.is-success {
  color: var(--play);
}

#file-status.is-error {
  color: var(--danger);
}

.sidebar,
.step-list-panel,
.saved-sequences-panel {
  min-width: 0;
}

.sidebar {
  display: grid;
  gap: 16px;
}

.saved-sequences-list {
  display: grid;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.saved-sequence-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px;
  background: var(--surface-raised);
}

.saved-sequence-details {
  min-width: 0;
}

.saved-sequence-name {
  display: block;
  overflow: hidden;
  font-size: 0.88rem;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.saved-sequence-meta,
.saved-sequences-empty {
  color: var(--muted);
  font-size: 0.72rem;
}

.saved-sequence-actions {
  display: flex;
  gap: 6px;
}

.saved-sequence-button {
  min-height: 40px;
  border: 1px solid var(--border-strong);
  border-radius: 5px;
  padding: 0 10px;
  font-size: 0.76rem;
  font-weight: 800;
  cursor: pointer;
  background: var(--surface);
}

.saved-sequence-button:hover {
  border-color: #737d8d;
  background: var(--surface-active);
}

.saved-sequence-button.delete {
  color: var(--danger);
}

.saved-indicator {
  color: var(--muted);
  font-size: 0.72rem;
}

.saved-indicator.is-saving {
  color: var(--accent);
}

.step-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  grid-template-rows: repeat(var(--list-rows), auto);
  grid-auto-flow: column;
  gap: 4px 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.step-list-button {
  display: grid;
  grid-template-columns: 2.2rem minmax(3.8rem, 1fr) 2.3rem;
  align-items: center;
  width: 100%;
  min-height: 40px;
  border: 1px solid transparent;
  border-radius: 4px;
  padding: 0 8px;
  color: var(--text);
  text-align: left;
  cursor: pointer;
  background: transparent;
}

.step-list-button:hover {
  background: var(--surface-raised);
}

.step-list-button.is-selected {
  border-color: var(--accent);
  background: var(--surface-raised);
}

.step-list-button.is-playing {
  color: #0b1710;
  background: var(--play);
}

.list-number,
.list-note,
.list-legato {
  font: 700 0.83rem/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.list-number {
  color: var(--muted);
}

.step-list-button.is-playing .list-number {
  color: #294331;
}

.list-legato {
  color: var(--accent);
  font-size: 0.67rem;
}

.step-list-button.is-playing .list-legato {
  color: #294331;
}

footer {
  display: grid;
  gap: 6px;
  padding: 4px 16px 28px;
  text-align: center;
}

footer .copyright {
  color: var(--text);
  font-size: 0.74rem;
}

@media (min-width: 520px) {
  .header-inner {
    grid-template-columns: 1fr 1fr;
  }

  .brand-block,
  .global-controls {
    grid-column: 1 / -1;
  }

  .global-controls {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .global-controls .field:nth-child(3) {
    grid-column: auto;
  }

  .steps-grid {
    grid-template-columns: repeat(8, minmax(0, 1fr));
  }

  .section-hint {
    display: block;
  }

  .export-row {
    grid-template-columns: 1fr auto;
    align-items: center;
  }

  .file-actions {
    display: flex;
  }

  .export-button {
    grid-column: auto;
  }

  .step-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    grid-template-rows: none;
    grid-auto-flow: row;
  }
}

@media (min-width: 960px) {
  .header-inner {
    grid-template-columns: auto minmax(230px, 1fr) auto minmax(300px, 1fr);
    align-items: end;
    padding: 18px 24px;
  }

  .brand-block,
  .global-controls {
    grid-column: auto;
  }

  .brand-block h1 {
    font-size: 1.55rem;
  }

  .transport {
    grid-template-columns: auto auto;
  }

  .transport-status {
    display: none;
  }

  .app-layout {
    grid-template-columns: minmax(0, 2fr) minmax(300px, 0.8fr);
    align-items: start;
    padding: 24px;
  }

  .panel,
  .export-row {
    padding: 20px;
  }

  .sidebar {
    position: sticky;
    top: 16px;
    max-height: calc(100vh - 32px);
    overflow: auto;
  }

  .step-list {
    grid-template-columns: 1fr;
    grid-template-rows: none;
    grid-auto-flow: row;
  }

  .piano {
    height: 190px;
  }
}

@media (prefers-reduced-motion: no-preference) {
  .step-button,
  .transport-button,
  .action-button,
  .file-button,
  .export-button {
    transition: border-color 100ms ease, background-color 100ms ease, color 100ms ease;
  }
}