:root {
  --bg: #14121c;
  --panel: #1f1c2b;
  --cell: #2c2840;
  --text: #ece9f5;
  --muted: #8f89a8;
  --accent: #ff5c8a;
  --drum: #ffb547;
  --melody: #4fd1c5;
  --playhead: rgba(255, 255, 255, .12);
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: system-ui, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
}
.top { padding: 20px 24px 4px; }
.top h1 { margin: 0; font-size: 1.8rem; }
.hint { margin: 4px 0 0; color: var(--muted); }

.layout {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 20px;
  padding: 20px 24px;
}
@media (max-width: 860px) { .layout { grid-template-columns: 1fr; } }

.studio, .library {
  background: var(--panel);
  border-radius: 16px;
  padding: 18px;
}

.controls, .save-row {
  display: flex; flex-wrap: wrap; gap: 10px; align-items: center;
}
.controls { margin-bottom: 16px; }
.save-row { margin-top: 16px; }

.btn {
  border: 0; border-radius: 10px; padding: 10px 16px;
  background: var(--cell); color: var(--text);
  font-size: .95rem; cursor: pointer;
}
.btn:hover { filter: brightness(1.2); }
.btn.primary { background: var(--accent); color: #fff; font-weight: 600; }
.tempo { display: flex; gap: 8px; align-items: center; color: var(--muted); }
.tempo input { accent-color: var(--accent); }

input[type=text] {
  flex: 1; min-width: 160px;
  padding: 10px 12px; border-radius: 10px;
  border: 1px solid var(--cell); background: var(--bg); color: var(--text);
}
.status { color: var(--muted); font-size: .9rem; }

/* Grid */
.grid { overflow-x: auto; }
.row { display: flex; align-items: center; gap: 4px; margin-bottom: 4px; }
.row.gap { margin-top: 12px; }
.label {
  width: 64px; flex: none; font-size: .8rem; color: var(--muted);
  text-align: right; padding-right: 8px;
}
.cell {
  flex: 1 0 28px; height: 32px; min-width: 28px;
  border: 0; border-radius: 6px; background: var(--cell);
  cursor: pointer; transition: transform .08s;
}
.cell:nth-of-type(4n+2) { margin-left: 4px; } /* group in beats */
.cell:hover { filter: brightness(1.3); }
.cell.on.drum { background: var(--drum); }
.cell.on.melody { background: var(--melody); }
.cell.now { outline: 2px solid var(--playhead); box-shadow: 0 0 0 100px var(--playhead) inset; }
.cell.on.now { transform: scale(1.12); }

/* Library */
.library h2 { margin: 0 0 12px; font-size: 1.1rem; }
#trackList { list-style: none; margin: 0; padding: 0; }
#trackList li {
  display: flex; justify-content: space-between; align-items: center;
  padding: 10px; border-radius: 8px; cursor: pointer;
}
#trackList li:hover { background: var(--cell); }
#trackList li.active { background: var(--cell); outline: 1px solid var(--accent); }
#trackList .empty { color: var(--muted); cursor: default; }
#trackList .del {
  background: none; border: 0; color: var(--muted); cursor: pointer; font-size: 1rem;
}
#trackList .del:hover { color: var(--accent); }