:root {
  --bg: #f5f6f8;
  --panel: #ffffff;
  --border: #dde1e6;
  --text: #1f2430;
  --muted: #6b7280;
  --accent: #4C6EF5;
  --track-empty: #e9ecef;
  --track-empty-stripe: #dfe3e8;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  background: var(--bg);
  color: var(--text);
}

header.topnav {
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 14px 24px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 10;
}

header.topnav h1 {
  font-size: 16px;
  margin: 0;
  margin-right: auto;
  color: var(--text);
}

header.topnav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  padding: 6px 12px;
  border-radius: 6px;
}

header.topnav a.active {
  color: var(--accent);
  background: #eef1ff;
  font-weight: 600;
}

header.topnav a:hover { background: #f0f1f4; }

.auth-user-info {
  font-size: 13px;
  color: var(--muted);
}

.auth-gate {
  display: flex;
  position: fixed;
  inset: 0;
  background: rgba(245, 246, 248, 0.96);
  z-index: 100;
  align-items: center;
  justify-content: center;
}

.auth-gate-box {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 32px;
  max-width: 360px;
  text-align: center;
  box-shadow: 0 8px 24px rgba(31, 36, 48, 0.08);
}

.auth-gate-box h2 {
  margin-top: 0;
  font-size: 18px;
}

.auth-gate-box p {
  font-size: 13px;
  color: var(--muted);
}

.auth-gate-status {
  min-height: 16px;
  color: #d64545 !important;
}

main {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  margin-bottom: 20px;
}

.panel h2 {
  margin-top: 0;
  font-size: 15px;
  color: var(--muted);
  letter-spacing: 0.02em;
}

.form-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: flex-end;
  margin-bottom: 12px;
}

.field { display: flex; flex-direction: column; gap: 4px; }
.field label { font-size: 12px; color: var(--muted); }
.field input {
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 14px;
  min-width: 140px;
}

button {
  cursor: pointer;
  border: none;
  border-radius: 6px;
  padding: 8px 16px;
  font-size: 14px;
  background: var(--accent);
  color: white;
  font-weight: 600;
}

button.secondary {
  background: #eef0f4;
  color: var(--text);
}

button.danger {
  background: #fdeceb;
  color: #d64545;
}

button.icon {
  padding: 4px 8px;
  font-size: 12px;
}

button:disabled { opacity: 0.5; cursor: not-allowed; }

.timeline-wrap { display: none; }
.timeline-wrap.active { display: block; }

.ruler {
  position: relative;
  height: 12px;
  margin-bottom: 4px;
  font-size: 10px;
  color: var(--muted);
}
.ruler span {
  position: absolute;
  transform: translateX(-50%);
}
.ruler span:first-child { transform: translateX(0); }
.ruler span:last-child { transform: translateX(-100%); }

.select-track {
  position: relative;
  height: 40px;
  background: var(--track-empty);
  border-radius: 8px;
  border: 1px solid var(--border);
  cursor: crosshair;
  user-select: none;
  overflow: hidden;
  touch-action: none;
}

.select-track .hint {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  color: var(--muted);
  pointer-events: none;
}

.select-preview {
  position: absolute;
  top: 0;
  bottom: 0;
  background: rgba(76, 110, 245, 0.35);
  border: 1px solid var(--accent);
  border-radius: 4px;
  display: none;
}

.add-segment-form {
  display: none;
  margin-top: 12px;
  padding: 12px;
  background: #f8f9ff;
  border: 1px solid #d8ddf9;
  border-radius: 8px;
  gap: 10px;
  align-items: flex-end;
  flex-wrap: wrap;
}
.add-segment-form.active { display: flex; }

.segment-list { margin-top: 16px; display: flex; flex-direction: column; gap: 8px; }

.segment-row {
  display: grid;
  grid-template-columns: 110px 1fr 90px;
  align-items: center;
  gap: 10px;
}

.segment-row .seg-label {
  font-size: 13px;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.segment-row .seg-time {
  font-size: 11px;
  color: var(--muted);
  text-align: right;
}

.track {
  position: relative;
  height: 22px;
  background: var(--track-empty);
  background-image: repeating-linear-gradient(
    45deg, var(--track-empty-stripe), var(--track-empty-stripe) 4px, var(--track-empty) 4px, var(--track-empty) 8px
  );
  border-radius: 5px;
  overflow: hidden;
}

.track .fill {
  position: absolute;
  top: 0;
  bottom: 0;
  border-radius: 5px;
}

.song-list, .overview-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.song-card {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 14px;
  display: flex;
  align-items: center;
  gap: 12px;
  background: #fbfbfc;
}

.song-card .swatch {
  width: 10px;
  height: 32px;
  border-radius: 3px;
  flex-shrink: 0;
}

.song-card .info { flex: 1; min-width: 0; }
.song-card .info .name { font-weight: 600; font-size: 14px; }
.song-card .info .meta { font-size: 12px; color: var(--muted); }

.song-card .actions { display: flex; gap: 6px; flex-shrink: 0; }

.empty-note {
  color: var(--muted);
  font-size: 13px;
  padding: 16px 0;
  text-align: center;
}

.overview-block {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  margin-bottom: 14px;
  background: #fbfbfc;
}

.overview-block .head {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}

.overview-block .head .swatch {
  width: 12px;
  height: 12px;
  border-radius: 3px;
  flex-shrink: 0;
}

.overview-block .head .name {
  font-weight: 700;
  font-size: 14px;
  flex: 1;
}

.overview-block .head .meta {
  font-size: 12px;
  color: var(--muted);
}

.overview-block .head .reorder { display: flex; gap: 4px; }

.overview-block .song-track { margin-bottom: 8px; }

.overview-block .sub-rows { display: flex; flex-direction: column; gap: 6px; padding-left: 4px; }

.section-heading {
  margin: 0 0 12px;
  font-size: 15px;
  color: var(--muted);
  letter-spacing: 0.02em;
}

.song-order-list { display: flex; flex-direction: column; }

.song-order-row {
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}
.song-order-row:last-child { border-bottom: none; }

.overview-block .sub-row {
  display: grid;
  grid-template-columns: 110px 1fr;
  align-items: center;
  gap: 10px;
}
.overview-block .sub-row .seg-label {
  font-size: 12px;
  color: var(--text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.overview-block .sub-row .track { height: 16px; }

.track .song-boundary {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 2px;
  background: rgba(31, 36, 48, 0.4);
  z-index: 2;
}

.total-bar-wrap { margin-bottom: 24px; }
.total-bar-wrap .track { height: 10px; background: var(--track-empty); }
.total-meta { display: flex; justify-content: space-between; font-size: 12px; color: var(--muted); margin-bottom: 6px; }

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 10px;
}
.legend .chip {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: var(--muted);
}
.legend .chip .dot { width: 10px; height: 10px; border-radius: 3px; }

.label-color-panel {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.label-color-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

.label-color-row input[type="color"] {
  width: 28px;
  height: 28px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 6px;
  cursor: pointer;
  background: none;
}

.label-color-name {
  font-size: 13px;
  font-weight: 600;
}

.label-category-input {
  width: 100px;
  padding: 5px 8px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 12px;
}

.row-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  padding-left: 114px;
  margin-top: -2px;
}
.row-legend .chip {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 11px;
  color: var(--muted);
}
.row-legend .chip .dot { width: 8px; height: 8px; border-radius: 2px; flex-shrink: 0; }