:root {
  --body-bg: #d9dde3;
  --panel-bg: #eef0f3;
  --panel-bg-dark: #c7cbd2;
  --accent: #7a4de0;
  --accent-soft: rgba(122, 77, 224, 0.15);
  --op: #f0a53d;
  --eq: #e2582b;
  --text: #24262b;
  --text-soft: #5a6270;
  --shadow: rgba(0, 0, 0, 0.25);
  color-scheme: light;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(circle at 50% -10%, #f4f5f7 0%, var(--body-bg) 60%, #babfc7 100%);
  font-family: "Hiragino Sans", "Helvetica Neue", Arial, "Yu Gothic", sans-serif;
  color: var(--text);
  display: flex;
  justify-content: center;
  padding: 24px 12px 60px;
}

.page {
  width: 100%;
  max-width: 980px;
}

h1 {
  text-align: center;
  font-size: 1.4rem;
  margin: 4px auto 10px;
}

.lede {
  max-width: 640px;
  margin: 0 auto 20px;
  text-align: center;
  font-size: 0.85rem;
  line-height: 1.6;
  color: var(--text-soft);
}
.lede a { color: var(--accent); }

/* ---------- Drop zone ---------- */
.drop-zone {
  max-width: 520px;
  margin: 0 auto 24px;
  padding: 28px 20px;
  text-align: center;
  background: linear-gradient(180deg, var(--panel-bg), var(--panel-bg-dark));
  border: 2px dashed rgba(122, 77, 224, 0.5);
  border-radius: 18px;
  box-shadow: 0 12px 28px var(--shadow), inset 0 1px 0 rgba(255,255,255,0.6);
  transition: border-color 0.15s ease, background 0.15s ease;
}
.drop-zone.dragover {
  border-color: var(--accent);
  background: linear-gradient(180deg, #f4effe, var(--panel-bg-dark));
}
.drop-main { font-weight: 700; margin: 0 0 6px; }
.drop-sub { margin: 0 0 10px; font-size: 0.8rem; color: var(--text-soft); }
.file-btn {
  display: inline-block;
  padding: 10px 20px;
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  border-radius: 999px;
  cursor: pointer;
  box-shadow: 0 3px 0 rgba(0,0,0,0.2);
}
.file-btn:active { transform: translateY(2px); box-shadow: none; }
.drop-error {
  margin: 12px 0 0;
  color: #b3261e;
  font-size: 0.8rem;
  font-weight: 700;
}

/* ---------- Player ---------- */
.player {
  background: linear-gradient(180deg, var(--panel-bg), var(--panel-bg-dark));
  border-radius: 22px;
  padding: 20px;
  box-shadow: 0 18px 40px var(--shadow), inset 0 1px 0 rgba(255,255,255,0.6);
}

.song-info { margin-bottom: 14px; }
.song-name { font-weight: 700; font-size: 1.05rem; word-break: break-all; }
.song-meta { font-size: 0.78rem; color: var(--text-soft); margin-top: 2px; }

.roll-wrap {
  background: #1c2733;
  border-radius: 10px;
  padding: 6px;
  box-shadow: inset 0 3px 8px rgba(0,0,0,0.4);
  margin-bottom: 16px;
  cursor: pointer;
  overflow: hidden;
}
#pianoRoll { display: block; width: 100%; height: 220px; }

.transport {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-bottom: 18px;
}

.tbtn {
  width: 46px;
  height: 46px;
  border: none;
  border-radius: 50%;
  background: #fff;
  font-size: 1.1rem;
  cursor: pointer;
  box-shadow: 0 3px 0 rgba(0,0,0,0.25), 0 4px 6px rgba(0,0,0,0.15);
}
.tbtn:active { transform: translateY(2px); box-shadow: 0 1px 0 rgba(0,0,0,0.2); }
.tbtn-play { background: var(--accent); color: #fff; }
.tbtn-play.is-playing::before { content: "⏸"; }

.time-display {
  font-family: "Courier New", monospace;
  font-size: 0.95rem;
  min-width: 90px;
}

.control-group {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.78rem;
  color: var(--text-soft);
}
.control-group input[type="range"] { width: 100px; }
#speedVal { min-width: 44px; }

/* ---------- Track list ---------- */
.track-list { display: flex; flex-direction: column; gap: 6px; }

.track-row {
  display: grid;
  grid-template-columns: 12px 1fr auto 90px;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  background: rgba(255,255,255,0.5);
  border-radius: 10px;
  font-size: 0.8rem;
}
.track-row.is-muted { opacity: 0.5; }
.track-swatch {
  width: 12px;
  height: 12px;
  border-radius: 3px;
}
.track-label {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.track-count { color: var(--text-soft); font-size: 0.72rem; }
.track-toggle {
  border: none;
  border-radius: 6px;
  padding: 4px 9px;
  font-size: 0.72rem;
  font-weight: 700;
  cursor: pointer;
  background: #e2e5ea;
  color: var(--text-soft);
}
.track-toggle + .track-toggle { margin-left: 4px; }
.track-toggle.on.mute-on { background: var(--eq); color: #fff; }
.track-toggle.on.solo-on { background: var(--op); color: #3a2200; }
.track-toggles { white-space: nowrap; }
.track-row input[type="range"] { width: 90px; }

/* ---------- Legend ---------- */
.legend {
  max-width: 640px;
  margin: 26px auto 0;
  font-size: 0.85rem;
  line-height: 1.6;
  color: #33363c;
}
.legend summary { cursor: pointer; font-size: 1rem; font-weight: 700; margin-bottom: 8px; }
.legend ul { padding-left: 1.2em; margin: 0; }

@media (max-width: 480px) {
  .track-row {
    grid-template-columns: 10px 1fr;
    grid-template-areas: "sw label" "toggles toggles" "vol vol";
  }
  .track-swatch { grid-area: sw; }
  .track-label { grid-area: label; }
  .track-toggles { grid-area: toggles; }
  .track-row input[type="range"] { grid-area: vol; width: 100%; }
}