:root {
  --accent: #d9ff3f;
  --accent-soft: #efff9a;
  --bg-top: #ece9e1;
  --bg-bottom: #ece9e1;
  --surface: #f7f4ee;
  --surface-strong: #ffffff;
  --line: rgba(80, 70, 58, 0.16);
  --line-strong: rgba(50, 43, 36, 0.28);
  --text: #171411;
  --text-soft: #6f685f;
  --confirmed-bg: #eef9c9;
  --confirmed-border: rgba(122, 142, 43, 0.42);
  --tentative-bg: #fff2cf;
  --tentative-border: rgba(187, 141, 40, 0.38);
  --hold-bg: #ece7df;
  --danger: #b04b3b;
  --radius-xl: 8px;
  --radius-lg: 6px;
  --radius: 5px;
  --radius-sm: 4px;
  --shadow: none;
  --shadow-soft: none;
  font-family: "Avenir Next", "Hiragino Sans", "Yu Gothic", sans-serif;
  color-scheme: light;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  color: var(--text);
  background: var(--bg-top);
  position: relative;
  overflow-x: hidden;
}

body::before,
body::after {
  content: none;
}

#start-screen,
#main-screen {
  position: relative;
  z-index: 1;
}

#start-screen[hidden],
#main-screen[hidden],
#settings-panel[hidden] {
  display: none !important;
}

button,
input[type="text"] {
  font: inherit;
}

button {
  cursor: pointer;
  min-height: 46px;
  padding: 0.7rem 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  color: var(--text);
  line-height: 1.2;
  transition:
    background-color 0.18s ease,
    border-color 0.18s ease,
    color 0.18s ease;
  box-shadow: none;
}

button:hover {
  border-color: var(--line-strong);
  box-shadow: none;
}

button:active {
  transform: none;
}

button:focus-visible,
input[type="text"]:focus-visible {
  outline: 2px solid var(--text);
  outline-offset: 3px;
}

button:disabled {
  cursor: default;
  opacity: 0.45;
  transform: none;
  box-shadow: none;
}

input[type="text"] {
  width: 100%;
  min-height: 54px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  color: var(--text);
  padding: 0.9rem 1.1rem;
  box-shadow: none;
}

.hint {
  display: block;
  margin-top: 0.65rem;
  font-size: 0.86rem;
  color: var(--text-soft);
}

.chip-row,
.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.chip-row button,
.chip {
  min-height: 38px;
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
}

.chip-row button.active,
.chip-row button:hover,
.chip:hover {
  background: var(--accent-soft);
  border-color: rgba(118, 135, 44, 0.34);
  color: var(--text);
}

.chip-sm button {
  min-height: 34px;
  padding: 0.35rem 0.7rem;
  font-size: 0.82rem;
}

.key-grid button {
  min-width: 54px;
  justify-content: center;
}

#start-screen {
  padding: 1.75rem 1.25rem 3rem;
}

.start-wrap {
  width: min(760px, 100%);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.8rem;
  align-items: start;
}

.app-header,
.start-block,
#top-bar,
#song-toolbar,
#song-library-panel,
#lyrics-area,
#piano-area,
#settings-panel,
#timeline-area,
#bar-nav,
#candidate-area,
#action-area,
#recent-area,
#progression-area {
  background: var(--surface);
  backdrop-filter: none;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.app-header {
  min-height: auto;
  border-radius: var(--radius-lg);
  padding: 0.95rem 1rem;
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  justify-content: flex-start;
}

.app-header::before {
  content: none;
}

.app-header::after {
  content: none;
}

.app-header__top,
.app-header__hero {
  position: relative;
  z-index: 1;
}

.app-header__top {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 0.6rem;
}

.brand-chip {
  display: inline-flex;
  align-items: center;
  min-height: 2rem;
  padding: 0.35rem 0.7rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.58);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.app-header__hero {
  width: 100%;
  padding-top: 0;
}

.hero-kicker {
  margin-bottom: 0.9rem;
  font-size: 0.85rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-soft);
}

.app-header h1 {
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  line-height: 1;
  letter-spacing: -0.06em;
  margin-bottom: 0.35rem;
  width: 100%;
}

.hero-copy {
  font-size: 0.94rem;
  color: var(--text-soft);
  max-width: none;
}

.start-settings-header {
  display: none;
}

.start-block {
  border-radius: var(--radius-lg);
  padding: 1.1rem;
  position: relative;
  overflow: hidden;
}

.start-block::before {
  content: "";
  position: absolute;
  inset: auto auto -3rem -3rem;
  width: 8rem;
  height: 8rem;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(217, 255, 63, 0.22), transparent 70%);
  pointer-events: none;
}

.start-block--chord,
.start-block--tendency,
.start-block--key,
.start-block--meter {
  grid-column: auto;
  grid-row: auto;
}

.chord-select-label,
.section-label {
  margin-bottom: 0.95rem;
  font-size: 0.83rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-soft);
}

.label-sub {
  letter-spacing: 0;
  text-transform: none;
  font-size: 0.8rem;
}

.starter-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.65rem;
  margin-bottom: 0.85rem;
}

.starter-btn,
.mood-btn,
.key-status-btn,
.key-btn,
.time-signature-btn {
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.54);
  border: 1px solid var(--line);
  color: var(--text);
}

.time-signature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.55rem;
}

.time-signature-btn {
  min-height: 3.2rem;
  font-size: 0.98rem;
  font-weight: 600;
}

.starter-btn {
  min-height: 4.2rem;
  font-size: 1.08rem;
  font-weight: 600;
  letter-spacing: -0.03em;
}

.starter-btn.active,
.time-signature-btn.active,
.mood-btn.active,
.key-status-btn.active,
.key-btn.active,
.btn-start-go {
  background: linear-gradient(180deg, var(--accent), #cdf021);
  border-color: rgba(107, 124, 30, 0.42);
  color: #18150f;
  box-shadow: none;
}

.mood-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.6rem;
}

.mood-btn {
  min-height: 3.9rem;
  font-weight: 600;
  font-size: 0.96rem;
}

.key-status-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.55rem;
  margin-bottom: 0.75rem;
}

.key-status-btn {
  min-height: 3.35rem;
  font-size: 0.95rem;
}

.key-btn-grid {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0.5rem;
}

.key-btn {
  min-height: 3rem;
  min-width: 0;
  padding-inline: 0.4rem;
  font-size: 0.88rem;
  font-weight: 600;
}

.starter-input-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.65rem;
}

.btn-start-go {
  min-width: 8rem;
  font-weight: 700;
}

.btn-skip {
  grid-column: 1 / -1;
  border-radius: var(--radius-lg);
  min-height: 3.5rem;
  background: rgba(23, 20, 17, 0.92);
  border-color: rgba(23, 20, 17, 0.92);
  color: #f8f4ec;
  font-weight: 600;
}

.btn-skip:hover {
  background: rgba(23, 20, 17, 0.82);
  border-color: rgba(23, 20, 17, 0.82);
}

#main-screen {
  width: min(1160px, calc(100% - 1.25rem));
  margin: 0 auto;
  padding: 0.55rem 0 2rem;
}

body.help-open {
  overflow: hidden;
}

#main-screen::before {
  content: none;
}

#top-bar {
  position: static;
  z-index: 20;
  border-radius: var(--radius-lg);
  padding: 0.4rem 0.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.65rem;
  margin-bottom: 0.6rem;
}

#song-toolbar,
#youtube-panel,
#song-library-panel,
#assist-toolbar {
  border-radius: var(--radius-lg);
  padding: 0.68rem;
  margin-bottom: 0.7rem;
}

.song-toolbar-main {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.6rem;
  align-items: end;
}

#assist-toolbar {
  margin-top: 0.5rem;
  margin-bottom: 0;
  display: block;
  padding: 0;
}

#youtube-panel {
  display: grid;
  gap: 0.5rem;
}

#youtube-panel[hidden] {
  display: none !important;
}

.youtube-toolbar {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.55rem;
}

.youtube-url-wrap {
  display: grid;
  gap: 0.28rem;
}

#youtube-url-input {
  min-height: 2rem;
  padding: 0.42rem 0.68rem;
  font-size: 0.8rem;
}

.youtube-toolbar-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.28rem;
  align-items: end;
}

.youtube-rate-wrap {
  display: grid;
  gap: 0.22rem;
}

#youtube-rate-select {
  min-height: 1.95rem;
  padding: 0.34rem 0.5rem;
  font-size: 0.78rem;
  min-width: 5.6rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: #fff;
  color: var(--text-main);
}

#youtube-player-shell {
  position: relative;
  width: 100%;
  border: 1px solid rgba(72, 62, 51, 0.08);
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: #000;
  aspect-ratio: 16 / 9;
  min-height: 200px;
}

#youtube-panel.compact-player #youtube-player-shell {
  width: min(320px, 100%);
  height: 200px;
  min-height: 200px;
  max-width: 100%;
  aspect-ratio: auto;
  justify-self: start;
}

#youtube-player,
#youtube-player iframe {
  width: 100%;
  height: 100%;
  display: block;
}

.song-toolbar-fields {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 6.8rem;
  gap: 0.5rem;
  align-items: end;
}

.song-title-wrap {
  display: grid;
  gap: 0.28rem;
}

.song-bpm-wrap {
  display: grid;
  gap: 0.28rem;
}

.song-toolbar-label {
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-soft);
}

#song-title-input {
  min-height: 2rem;
  padding: 0.42rem 0.68rem;
  font-size: 0.8rem;
}

#song-bpm-input {
  min-height: 2rem;
  padding: 0.42rem 0.58rem;
  font-size: 0.8rem;
  text-align: center;
}

.assist-toggle-row,
.transpose-row {
  display: flex;
  gap: 0.35rem;
  flex-wrap: wrap;
  align-items: center;
}

.transpose-row {
  justify-content: flex-end;
}

.transpose-inline {
  margin-left: auto;
  justify-content: flex-end;
}

.transpose-inline .song-toolbar-label {
  margin-right: 0.08rem;
}

.assist-toggle-row .btn-sm.active,
#lyrics-voice-btn.active {
  background: rgba(239, 255, 154, 0.92);
  border-color: rgba(121, 139, 40, 0.4);
}

#transpose-key-select,
.lyrics-section-input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: #fff;
  color: var(--text-main);
}

#transpose-key-select {
  min-height: 1.95rem;
  padding: 0.34rem 0.5rem;
  font-size: 0.78rem;
  width: 8rem;
}

#lyrics-area,
#piano-area {
  display: none;
}

#timeline-area .timeline-system-extra {
  grid-column: 1 / -1;
}

#timeline-area .timeline-system-guitar {
  margin-top: -0.08rem;
}

#timeline-area .timeline-system-piano {
  margin-top: -0.08rem;
}

#timeline-area .timeline-system-lyrics {
  margin-top: -0.16rem;
}

.timeline-guitar-grid {
  display: grid;
  gap: 0.28rem;
}

.timeline-guitar-bar {
  min-width: 0;
}

.timeline-guitar-beat-grid {
  display: grid;
  gap: 0.08rem;
}

.mini-guitar-slot {
  min-height: 3.4rem;
  padding: 0.08rem 0.12rem 0.02rem;
  border: 1px solid rgba(72, 62, 51, 0.08);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.88);
}

.mini-guitar-slot.current {
  box-shadow: inset 0 0 0 1px rgba(99, 200, 199, 0.72);
}

.mini-guitar-slot.empty {
  border-color: transparent;
  background: transparent;
}

.mini-guitar-card {
  display: grid;
  place-items: center;
}

.mini-guitar-svg {
  width: 100%;
  max-width: 4.85rem;
  height: 2.95rem;
  display: block;
}

.mini-guitar-string,
.mini-guitar-fret,
.mini-guitar-nut {
  stroke: rgba(54, 48, 40, 0.28);
}

.mini-guitar-string,
.mini-guitar-fret {
  stroke-width: 1;
}

.mini-guitar-nut {
  stroke-width: 2.1;
}

.mini-guitar-dot {
  fill: rgba(129, 204, 255, 0.85);
  stroke: rgba(86, 171, 223, 0.92);
  stroke-width: 1.2;
}

.mini-guitar-barre {
  fill: rgba(129, 204, 255, 0.82);
  stroke: rgba(86, 171, 223, 0.92);
  stroke-width: 1;
}

.mini-guitar-open {
  fill: #fff;
  stroke: rgba(54, 48, 40, 0.7);
  stroke-width: 1.1;
}

.mini-guitar-mark,
.mini-guitar-basefret,
.mini-guitar-fretnum {
  fill: rgba(54, 48, 40, 0.82);
  font-size: 7px;
  font-weight: 700;
}

.timeline-piano-grid {
  display: grid;
  gap: 0.28rem;
}

.timeline-piano-bar {
  min-width: 0;
}

.timeline-piano-beat-grid {
  display: grid;
  gap: 0.08rem;
}

.mini-piano-slot {
  min-height: 5.18rem;
  padding: 0.02rem 0.08rem 0.08rem;
  border: 1px solid rgba(72, 62, 51, 0.08);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.85);
}

.mini-piano-slot.current {
  box-shadow: inset 0 0 0 1px rgba(99, 200, 199, 0.72);
}

.mini-piano-slot.empty {
  border-color: transparent;
  background: transparent;
}

.mini-staff-card {
  display: flex;
  justify-content: center;
  align-items: flex-start;
}

.mini-staff-host {
  width: 100%;
}

.mini-staff-svg {
  width: 100%;
  max-width: 3.76rem;
  height: 4.68rem;
  display: block;
}

.mini-staff-line,
.mini-staff-ledger {
  stroke: rgba(54, 48, 40, 0.18);
  stroke-width: 1;
}

.mini-staff-note {
  fill: rgba(255, 255, 255, 0.98);
  stroke: rgba(30, 29, 24, 0.92);
  stroke-width: 1.5;
}

.mini-staff-accidental {
  font-size: 13px;
  fill: rgba(54, 48, 40, 0.92);
  font-weight: 700;
}

.lyrics-system-grid {
  display: grid;
  gap: 0.28rem;
}

.lyrics-section-card {
  display: grid;
  gap: 0.08rem;
  min-width: 0;
  padding: 0;
  border: 0;
  background: transparent;
}

.lyrics-section-card.current .lyrics-section-input {
  border-color: rgba(99, 200, 199, 0.72);
  box-shadow: inset 0 0 0 1px rgba(99, 200, 199, 0.18);
}

.lyrics-section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.28rem;
}

.lyrics-section-label {
  font-size: 0.52rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-soft);
}

.lyrics-voice-inline {
  min-height: 1.32rem;
  padding: 0.08rem 0.42rem;
  font-size: 0.64rem;
  white-space: nowrap;
}

.lyrics-section-input {
  min-height: 1.45rem;
  height: 1.45rem;
  padding: 0.1rem 0.32rem;
  font-size: 0.7rem;
  line-height: 1.2;
  border-radius: 2px;
}

.song-toolbar-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.28rem;
  justify-content: flex-end;
}

.song-library-list {
  display: grid;
  gap: 0.4rem;
}

.song-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.5rem;
  align-items: center;
  padding: 0.5rem 0.55rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: #fff;
}

.song-item.current {
  border-color: rgba(121, 139, 40, 0.4);
  background: rgba(239, 255, 154, 0.18);
}

.song-item-meta {
  display: grid;
  gap: 0.14rem;
  min-width: 0;
}

.song-item-meta strong {
  font-size: 0.82rem;
  line-height: 1.2;
}

.song-item-meta span {
  font-size: 0.72rem;
  color: var(--text-soft);
}

.top-info {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  min-width: 0;
}

.tool-name-tag {
  display: inline-flex;
  align-items: center;
  min-height: 1.9rem;
  padding: 0.28rem 0.78rem;
  border: 1px solid rgba(72, 62, 51, 0.12);
  border-radius: var(--radius-sm);
  background: rgba(231, 239, 216, 0.78);
  color: #33411a;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.badge,
.btn-icon,
.btn-nav,
.btn-sm,
.chip {
  border-radius: var(--radius-sm);
}

.badge {
  min-height: 1.9rem;
  padding: 0.28rem 0.7rem;
  background: #fff;
  font-size: 0.76rem;
}

.badge-progress {
  background: rgba(217, 255, 63, 0.16);
  border-color: rgba(121, 139, 40, 0.28);
  font-weight: 700;
}

.badge-build {
  background: rgba(99, 200, 199, 0.08);
  border-color: rgba(99, 200, 199, 0.3);
  color: var(--text-soft);
  font-size: 0.68rem;
  letter-spacing: 0.06em;
}

.badge-help {
  background: rgba(255, 241, 188, 0.65);
  border-color: rgba(177, 142, 40, 0.28);
  font-weight: 700;
}

.badge-suggest {
  background: rgba(255, 248, 210, 0.9);
  border-color: rgba(197, 157, 48, 0.35);
  font-weight: 700;
}

.btn-icon {
  min-height: 1.95rem;
  padding: 0.3rem 0.7rem;
  background: #fff;
  white-space: nowrap;
}

#help-overlay {
  position: fixed;
  inset: 0;
  z-index: 80;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  background: rgba(19, 16, 13, 0.34);
  backdrop-filter: blur(4px);
}

#help-overlay[hidden] {
  display: none !important;
}

#help-modal {
  width: min(760px, calc(100% - 1rem));
  max-height: min(82vh, 760px);
  overflow: auto;
  border: 1px solid rgba(72, 62, 51, 0.1);
  border-radius: var(--radius-lg);
  background: #fbf8f1;
  box-shadow: 0 28px 80px rgba(25, 21, 17, 0.2);
  padding: 1rem 1rem 1.05rem;
}

.help-modal-header {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 0.8rem;
  margin-bottom: 0.85rem;
}

.help-kicker {
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-soft);
  margin-bottom: 0.2rem;
}

#help-modal-title {
  font-size: 1.05rem;
  letter-spacing: -0.03em;
}

.help-modal-body {
  display: grid;
  gap: 0.75rem;
}

.help-modal-footer {
  display: flex;
  justify-content: flex-end;
  padding: 0.8rem 0.2rem 0;
}

.help-modal-footer a {
  color: var(--text-secondary);
  font-size: 0.82rem;
  text-decoration: none;
}

.help-modal-footer a:hover {
  color: var(--text-primary);
  text-decoration: underline;
}

.help-section {
  padding: 0.72rem 0.78rem;
  border: 1px solid rgba(72, 62, 51, 0.08);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.75);
}

.help-section h3 {
  font-size: 0.82rem;
  margin-bottom: 0.38rem;
}

.help-list {
  margin: 0;
  padding-left: 1.05rem;
  display: grid;
  gap: 0.18rem;
  color: var(--text-soft);
  font-size: 0.79rem;
  line-height: 1.55;
}

#settings-panel {
  border-radius: var(--radius-lg);
  padding: 0.8rem 0.9rem;
  margin-bottom: 0.75rem;
}

.settings-body {
  display: grid;
  gap: 0.9rem;
}

.settings-row {
  display: grid;
  grid-template-columns: 6rem minmax(0, 1fr);
  gap: 0.75rem;
  align-items: start;
}

.settings-label {
  padding-top: 0.55rem;
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-soft);
}

.btn-danger-sm,
.btn-sm-danger {
  color: var(--danger);
  border-color: rgba(176, 75, 59, 0.26);
  background: rgba(255, 246, 244, 0.9);
}

#main-body {
  display: grid;
  grid-template-columns: minmax(0, 1.28fr) minmax(320px, 0.92fr);
  gap: 0.7rem;
  align-items: start;
}

#timeline-area,
#bar-nav,
#candidate-area,
#action-area,
#recent-area,
#progression-area,
#lyrics-area,
#piano-area {
  border-radius: var(--radius-lg);
  padding: 0.68rem;
  position: relative;
  overflow: hidden;
}

#timeline-area::before,
#candidate-area::before,
#recent-area::before,
#progression-area::before {
  content: none;
}

#timeline-area {
  grid-column: 1 / -1;
  order: 1;
  overflow: visible;
}

#lyrics-area {
  grid-column: 1 / -1;
  order: 2;
}

#candidate-area {
  grid-column: 1 / -1;
  order: 3;
}

#bar-nav {
  order: 4;
}

#action-area {
  order: 5;
}

#piano-area {
  grid-column: 1 / -1;
  order: 6;
}

#progression-area {
  grid-column: 1 / -1;
  order: 7;
}

.tl-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-bottom: 0.25rem;
  flex-wrap: wrap;
  padding: 0.1rem 0 0.38rem;
  background: rgba(247, 244, 236, 0.96);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid rgba(72, 62, 51, 0.08);
}

.tl-title-group {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  min-width: 0;
  flex-wrap: wrap;
}

.tl-header h3,
#recent-area h3 {
  font-size: 0.88rem;
  letter-spacing: -0.03em;
}

.timeline-recent {
  display: inline-flex;
  align-items: center;
  gap: 0.28rem;
  min-width: 0;
}

.timeline-recent-label {
  font-size: 0.62rem;
  color: var(--text-soft);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.timeline-recent-row {
  display: flex;
  align-items: center;
  gap: 0.22rem;
  flex-wrap: wrap;
}

.timeline-recent-row .chip {
  min-height: 1.62rem;
  padding: 0.14rem 0.52rem;
  font-size: 0.74rem;
  border-radius: 999px;
}

.tl-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.28rem;
}

.youtube-sticky-controls {
  width: 100%;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.3rem;
  padding-top: 0.28rem;
  margin-top: 0.1rem;
  border-top: 1px solid rgba(72, 62, 51, 0.08);
}

.youtube-sticky-controls[hidden] {
  display: none !important;
}

.youtube-rate-wrap-inline {
  display: inline-flex;
  align-items: center;
  gap: 0.34rem;
}

.youtube-rate-wrap-inline .song-toolbar-label {
  margin: 0;
}

#youtube-sticky-rate-select {
  min-height: 1.9rem;
  padding: 0.34rem 0.5rem;
  font-size: 0.78rem;
  min-width: 5.4rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: #fff;
  color: var(--text-main);
}

.youtube-sticky-status {
  font-size: 0.72rem;
  color: var(--text-soft);
  margin-left: auto;
}

.tl-actions .btn-sm.active {
  background: rgba(239, 255, 154, 0.92);
  border-color: rgba(121, 139, 40, 0.4);
}

.btn-sm {
  min-height: 1.9rem;
  padding: 0.24rem 0.54rem;
  font-size: 0.74rem;
  background: #fff;
}

#pattern-result {
  min-height: 0;
  margin-bottom: 0.18rem;
  font-size: 0.75rem;
}

.timeline {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.34rem 0.28rem;
  max-height: none;
  overflow: visible;
  padding: 0;
}

.bar-chip {
  position: relative;
  display: grid;
  gap: 0.16rem;
  min-height: auto;
  padding: 0;
  border: 0;
  background: transparent;
  text-align: left;
  box-shadow: none;
  overflow: visible;
}

.bar-chip.pattern-match {
  box-shadow: none;
}

.bar-chip.current .bar-num {
  color: var(--text);
  opacity: 0.95;
}

.bar-num {
  font-size: 0.56rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-soft);
  opacity: 0.82;
}

.measure-grid {
  position: relative;
  display: grid;
  grid-auto-rows: minmax(3.15rem, auto);
  align-items: stretch;
  min-height: 3.15rem;
  border: 1px solid rgba(72, 62, 51, 0.18);
  border-radius: 2px;
  overflow: hidden;
  background: #fff;
  isolation: isolate;
}

.bar-chip.confirmed .measure-grid {
  border-color: var(--confirmed-border);
}

.bar-chip.tentative .measure-grid {
  border-color: var(--tentative-border);
}

.bar-chip.hold .measure-grid {
  border-color: rgba(145, 134, 121, 0.34);
}

.bar-chip.current .measure-grid {
  box-shadow: 0 0 0 1px rgba(54, 47, 40, 0.16);
}

.bar-chip.copy-selected .measure-grid,
.bar-chip.copy-source .measure-grid {
  background: rgba(239, 255, 154, 0.12);
  box-shadow: inset 0 0 0 2px rgba(160, 179, 56, 0.92);
}

.bar-chip.copy-destination .measure-grid,
.bar-chip.copy-target .measure-grid {
  background: rgba(97, 159, 228, 0.08);
  box-shadow: inset 0 0 0 2px rgba(97, 159, 228, 0.78);
}

.bar-chip.pattern-match .measure-grid {
  box-shadow: inset 0 0 0 1px rgba(214, 126, 40, 0.5);
}

.bar-chip.system-start .measure-grid {
  border-left-width: 2px;
  border-left-color: rgba(69, 58, 47, 0.78);
}

.bar-chip.system-end .measure-grid {
  border-right-width: 2px;
  border-right-color: rgba(69, 58, 47, 0.42);
}

.beat-cell {
  grid-row: 1;
  position: relative;
  min-height: 3.15rem;
  padding: 0.12rem 0.12rem 0.12rem;
  border: 0;
  border-right: 1px solid rgba(87, 74, 59, 0.14);
  border-radius: 0;
  background: transparent;
  display: grid;
  grid-template-rows: auto;
  align-items: start;
  justify-items: start;
  color: var(--text);
  box-shadow: none;
  z-index: 1;
}

.beat-cell[data-last-beat="true"] {
  border-right: 0;
}

.beat-cell::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 0;
  background: transparent;
  pointer-events: none;
}

.beat-cell:hover {
  transform: none;
  background: rgba(243, 241, 236, 0.9);
  border-color: transparent;
  box-shadow: none;
}

.beat-cell.current-slot {
  background: rgba(99, 200, 199, 0.08);
  box-shadow: inset 0 0 0 2px rgba(99, 200, 199, 0.74);
  color: var(--text);
}

.beat-cell.multi-selected:not(.current-slot) {
  background: rgba(99, 200, 199, 0.06);
  box-shadow: inset 0 0 0 2px rgba(99, 200, 199, 0.42);
}

.beat-cell.drag-target {
  background: rgba(99, 200, 199, 0.14);
  box-shadow: inset 0 0 0 2px rgba(99, 200, 199, 0.82);
}

.beat-index {
  font-size: 0.5rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: inherit;
  opacity: 0.72;
}

.beat-chord {
  display: none;
}

.segment-layer {
  position: absolute;
  inset: 0.62rem 0.05rem 0.05rem;
  z-index: 2;
  pointer-events: none;
}

.segment-block {
  position: absolute;
  top: 0;
  bottom: 0;
  left: calc(((var(--start) - 1) * 100% / var(--beats)) + 0.05rem);
  width: calc((var(--length) * 100% / var(--beats)) - 0.1rem);
  min-width: calc((100% / var(--beats)) - 0.1rem);
  padding: 0.18rem 0.14rem;
  border: 1px solid rgba(72, 62, 51, 0.14);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.98);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  box-shadow: inset 0 -2px 0 rgba(145, 134, 121, 0.18);
  pointer-events: auto;
  cursor: grab;
}

.segment-block.multi-line {
  padding-top: 0.12rem;
  padding-bottom: 0.12rem;
}

.segment-block.confirmed {
  background: rgba(238, 249, 201, 0.96);
  border-color: var(--confirmed-border);
  box-shadow: inset 0 -2px 0 rgba(132, 168, 52, 0.92);
}

.segment-block.tentative {
  background: rgba(255, 242, 207, 0.96);
  border-color: var(--tentative-border);
  box-shadow: inset 0 -2px 0 rgba(205, 153, 48, 0.94);
}

.segment-block.hold {
  background: rgba(236, 231, 223, 0.98);
  border-color: rgba(145, 134, 121, 0.34);
  box-shadow: inset 0 -2px 0 rgba(145, 134, 121, 0.9);
}

.segment-block.current-segment {
  background: #403a34;
  border-color: rgba(44, 39, 35, 0.92);
  box-shadow: inset 0 -2px 0 #63c8c7;
  color: #f7f6f2;
}

.segment-block.multi-selected:not(.current-segment) {
  box-shadow:
    inset 0 -2px 0 rgba(99, 200, 199, 0.96),
    0 0 0 1px rgba(99, 200, 199, 0.4);
}

.segment-block.dragging {
  opacity: 0.5;
  cursor: grabbing;
}

.segment-chord {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.04rem;
  font-size: clamp(0.8rem, 1vw, 0.92rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
  word-break: break-word;
}

.segment-block.multi-line .segment-chord {
  font-size: clamp(0.62rem, 0.86vw, 0.76rem);
  line-height: 1.05;
}

.segment-chord-line {
  display: block;
  width: 100%;
}

.segment-block.multi-line .segment-chord-line:last-child {
  font-size: 0.62em;
  opacity: 0.72;
}

#piano-note-hint {
  margin-top: 0.18rem;
  font-size: 0.7rem;
}

#bar-nav {
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.7rem;
}

#bar-title {
  flex: 1;
  text-align: center;
}

#bar-number {
  display: block;
  font-size: clamp(0.72rem, 1vw, 0.84rem);
  letter-spacing: -0.02em;
  color: var(--text-soft);
}

#bar-status {
  display: block;
  min-height: 1em;
  margin-top: 0.06rem;
  font-size: 0.76rem;
  color: var(--text-soft);
}

.btn-nav {
  min-width: 5.25rem;
  min-height: 2.2rem;
  padding: 0.34rem 0.72rem;
  font-size: 0.82rem;
  font-weight: 700;
  background: #fff;
}

.prev-chord {
  grid-column: 1 / -1;
  padding-inline: 0.2rem;
  font-size: 0.76rem;
  color: var(--text-soft);
}

.prev-chord-inline {
  grid-column: auto;
  padding-inline: 0;
  margin: 0;
  font-size: 0.72rem;
  white-space: nowrap;
}

#candidate-area {
  grid-column: 1 / -1;
}

.candidate-title {
  margin-bottom: 0.35rem;
  font-size: 0.68rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-soft);
}

#candidate-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.38rem;
  margin-bottom: 0.45rem;
}

.candidate-btn {
  min-height: 1.95rem;
  padding: 0.22rem 0.2rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: #fff;
  font-size: clamp(0.8rem, 0.96vw, 0.9rem);
  font-weight: 600;
  letter-spacing: -0.04em;
  text-align: center;
}

.candidate-btn:hover {
  background: #f8f6f2;
}

.candidate-btn.selected {
  background: linear-gradient(180deg, var(--accent), rgba(239, 255, 154, 0.92));
  border-color: rgba(121, 139, 40, 0.4);
  color: #16130d;
}

.different-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.35rem;
}

.candidate-toolbar {
  display: inline-flex;
  align-items: center;
  gap: 0.32rem;
  flex-wrap: wrap;
}

.btn-different {
  min-height: 1.75rem;
  padding: 0.22rem 0.5rem;
  background: #fff;
}

.btn-ai {
  border-color: rgba(95, 144, 189, 0.28);
}

.btn-ai[disabled] {
  opacity: 0.55;
}

.round-hint {
  font-size: 0.72rem;
  color: var(--text-soft);
  white-space: nowrap;
}

.ai-status {
  margin-top: 0.35rem;
  font-size: 0.72rem;
}

#action-area {
  grid-column: 1 / -1;
  display: grid;
  gap: 0.3rem;
}

.manual-input-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.42rem;
  align-items: center;
}

.btn-confirm,
.btn-tentative,
.btn-hold {
  min-height: 1.95rem;
  padding: 0.22rem 0.58rem;
  border-radius: var(--radius-sm);
  font-size: 0.78rem;
  font-weight: 700;
  background: #fff;
  box-shadow: none;
}

#manual-input {
  min-height: 2rem;
  padding: 0.42rem 0.68rem;
  font-size: 0.8rem;
}

#manual-apply-btn {
  min-height: 2rem;
  padding-inline: 0.8rem;
  white-space: nowrap;
}

#slot-state-actions {
  margin-top: 0.2rem;
  display: inline-flex;
  gap: 0.34rem;
  justify-content: center;
  flex-wrap: wrap;
}

.btn-confirm.active,
.btn-tentative.active,
.btn-hold.active {
  border-color: rgba(50, 43, 36, 0.34);
}

.btn-confirm.active {
  background: rgba(238, 249, 201, 0.98);
}

.btn-tentative.active {
  background: rgba(255, 242, 207, 0.98);
  border-color: var(--tentative-border);
}

.btn-hold.active {
  background: rgba(236, 231, 223, 0.98);
}

#progression-area {
  display: grid;
  gap: 0.45rem;
}

.no-recent {
  font-size: 0.92rem;
  color: var(--text-soft);
}

#recent-area h3,
#progression-area .chips {
  position: relative;
  z-index: 1;
}

.analysis-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.6rem;
}

.analysis-summary {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.55;
  color: var(--text);
}

.analysis-points {
  margin: 0;
  padding-left: 1.05rem;
  display: grid;
  gap: 0.22rem;
  color: var(--text-soft);
  font-size: 0.82rem;
  line-height: 1.55;
}

.analysis-points:empty {
  display: none;
}

.theory-catalog {
  margin: 0.1rem 0 0;
  padding-top: 0.3rem;
  border-top: 1px dashed rgba(66, 58, 50, 0.2);
}

.theory-catalog summary {
  cursor: pointer;
  font-size: 0.78rem;
  color: var(--text-soft);
  user-select: none;
}

.theory-catalog-list {
  margin-top: 0.35rem;
  max-height: 12rem;
  overflow: auto;
}

.chips {
  margin-bottom: 0.7rem;
}

.chip {
  background: rgba(255, 255, 255, 0.72);
}

@media (max-width: 1100px) {
  .start-wrap {
    grid-template-columns: 1fr;
  }

  .manual-input-row {
    grid-template-columns: 1fr;
  }

  .start-settings-header,
  .app-header,
  .start-block--meter,
  .start-block--chord,
  .start-block--tendency,
  .start-block--key,
  .btn-skip {
    grid-column: auto;
    grid-row: auto;
  }

  .app-header {
    min-height: 16rem;
  }

  .app-header::after {
    font-size: clamp(3.6rem, 17vw, 6rem);
    bottom: 1rem;
  }

  #main-body {
    grid-template-columns: 1fr;
  }

  #candidate-area,
  #action-area,
  #progression-area,
  #lyrics-area,
  #piano-area {
    grid-column: 1;
  }

  .timeline {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  #start-screen {
    padding: 1rem 0.75rem 2rem;
  }

  #main-screen {
    width: min(100%, calc(100% - 1rem));
    padding-top: 0.6rem;
  }

  .app-header {
    min-height: 15rem;
    padding: 1rem;
  }

  .app-header::before {
    width: 6.5rem;
    right: 0.75rem;
    top: 1.4rem;
  }

  .app-header::after {
    left: 0.9rem;
    bottom: 0.8rem;
  }

  .app-header__top {
    align-items: center;
  }

  .start-block {
    padding: 1rem;
  }

  .starter-grid,
  .key-btn-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .starter-input-row,
  .settings-row,
  #action-buttons {
    grid-template-columns: 1fr;
  }

  .btn-start-go {
    width: 100%;
  }

  #top-bar {
    top: 0.5rem;
    border-radius: var(--radius-lg);
    flex-direction: column;
    align-items: stretch;
  }

  .top-info {
    width: 100%;
  }

  .tl-title-group {
    width: 100%;
  }

  .timeline-recent {
    width: 100%;
  }

  #timeline-area,
  #bar-nav,
  #candidate-area,
  #action-area,
  #song-toolbar,
  #song-library-panel,
  #progression-area,
  #lyrics-area,
  #piano-area,
  #settings-panel {
    padding: 0.75rem;
  }

  .song-toolbar-main {
    grid-template-columns: 1fr;
  }

  .song-toolbar-fields {
    grid-template-columns: 1fr;
  }

  .transpose-row {
    justify-content: stretch;
  }

  #transpose-key-select {
    width: 100%;
  }

  .song-toolbar-actions {
    justify-content: stretch;
  }

  .song-toolbar-actions .btn-sm {
    flex: 1 1 calc(50% - 0.28rem);
  }

  #bar-nav {
    flex-wrap: wrap;
  }

  .btn-nav {
    flex: 1;
    min-width: 0;
  }

  #bar-title {
    order: -1;
    width: 100%;
    margin-bottom: 0.3rem;
  }

  .timeline {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    overflow-x: visible;
    overflow-y: visible;
    padding-bottom: 0;
  }

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

  .candidate-btn {
    min-height: 2.45rem;
    font-size: 0.9rem;
  }

  .different-row {
    flex-direction: column;
    align-items: stretch;
  }

  .candidate-toolbar {
    width: 100%;
  }

  .round-hint {
    white-space: normal;
  }
}

@media (max-width: 520px) {
  .timeline {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.privacy-page {
  min-height: 100vh;
  background:
    radial-gradient(circle at top center, rgba(255, 255, 255, 0.54), transparent 28%),
    linear-gradient(180deg, #f2f0e8 0%, #e4e0d5 100%);
}

.policy-page {
  padding: 24px 12px;
}

.policy-shell {
  width: min(860px, 100%);
  margin: 0 auto;
}

.policy-hero,
.policy-card-page {
  border: 1px solid var(--border-default);
  border-radius: 12px;
  background: rgba(251, 251, 248, 0.96);
}

.policy-hero {
  padding: 22px 24px;
  background:
    radial-gradient(circle at 82% 16%, rgba(169, 206, 74, 0.12), transparent 22%),
    linear-gradient(135deg, rgba(231, 239, 216, 0.72), rgba(251, 251, 248, 0.96) 62%);
}

.policy-kicker {
  margin: 0 0 8px;
  color: #6c7c39;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.policy-hero h1 {
  margin: 0;
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  line-height: 1.2;
}

.policy-lead {
  margin: 10px 0 0;
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.75;
}

.policy-card-page {
  margin-top: 14px;
  padding: 22px 24px;
}

.policy-card-page a {
  color: #5e7d1d;
  text-decoration: none;
}

.policy-card-page a:hover {
  text-decoration: underline;
}

.policy-meta-list {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0 0 18px;
  border-bottom: 1px solid var(--border-default);
}

.policy-meta-list div {
  display: grid;
  gap: 2px;
}

.policy-meta-list dt {
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 700;
}

.policy-meta-list dd {
  margin: 0;
  font-size: 0.95rem;
}

.policy-section {
  padding-top: 18px;
}

.policy-section h2 {
  margin: 0;
  font-size: 1rem;
  line-height: 1.5;
}

.policy-section p {
  margin: 8px 0 0;
  color: var(--text-secondary);
  font-size: 0.9375rem;
  line-height: 1.8;
}

.policy-page-footer {
  display: flex;
  justify-content: flex-end;
  padding: 14px 2px 0;
}

.policy-page-footer a {
  color: var(--text-secondary);
  font-size: 0.875rem;
  text-decoration: none;
}

.policy-page-footer a:hover {
  color: var(--text-primary);
  text-decoration: underline;
}

@media (max-width: 720px) {
  .policy-page {
    padding: 16px 10px;
  }

  .policy-hero,
  .policy-card-page {
    padding-left: 16px;
    padding-right: 16px;
  }
}