:root {
  --ink: #111;
  --line: #111;
  --muted: #555;
  --hair: #ccc;
  --accent: #111;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Menlo, Consolas, "Courier New", monospace;
  font-size: 14px;
  line-height: 1.5;
  color: var(--ink);
  background: #fff;
}

main {
  max-width: 640px;
  margin: 0 auto;
  padding: 2rem 1rem 4rem;
}

header h1 {
  margin: 0;
  font-size: 1.2rem;
  font-weight: 700;
}
header p {
  margin: 0.25rem 0 1.5rem;
  color: var(--muted);
}

/* File input: a plain bordered bar, not a card. */
.drop {
  border: 1px solid var(--line);
  padding: 0.9rem 1rem;
  cursor: pointer;
  background: #fff;
}
.drop.hover {
  background: #f0f0f0;
}
.drop p {
  margin: 0.15rem 0;
}
.hint {
  color: var(--muted);
}
code {
  font-family: inherit;
}
code::before {
  content: "[";
}
code::after {
  content: "]";
}

/* Track list: simple hairline-separated rows. */
.tracks {
  margin: 1rem 0 0;
}
.track {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.45rem 0;
  border-bottom: 1px solid var(--hair);
}
.track-info {
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.track-info strong {
  font-weight: 700;
}
.track-info span {
  color: var(--muted);
}
select {
  font-family: inherit;
  font-size: inherit;
  padding: 0.15rem 0.3rem;
  border: 1px solid var(--line);
  background: #fff;
  color: inherit;
}

.fold {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 1rem 0 0;
  color: var(--muted);
  cursor: pointer;
}
.fold input {
  accent-color: var(--accent);
}

#play {
  font-family: inherit;
  font-size: inherit;
  margin-top: 1.25rem;
  padding: 0.4rem 1.4rem;
  border: 1px solid var(--accent);
  background: #fff;
  color: var(--accent);
  cursor: pointer;
}
#play:hover:not(:disabled) {
  background: var(--accent);
  color: #fff;
}
#play:disabled {
  color: var(--muted);
  border-color: var(--hair);
  cursor: not-allowed;
}

#status {
  margin: 0.9rem 0 0;
  min-height: 1.2em;
  color: var(--muted);
}
#status.ok {
  color: var(--accent);
}
#status.err {
  color: #b00;
}

.stage {
  margin-top: 1.5rem;
  border: 1px solid var(--line);
}
.stage iframe {
  display: block;
  width: 100%;
  height: min(90vh, 760px);
  min-height: 640px;
  border: 0;
}