:root {
  color-scheme: dark;
  --ink: #ece7ff;
  --muted: #9d95c9;
  --glass: rgba(12, 6, 24, 0.6);
  --line: rgba(255, 255, 255, 0.12);
  --accent: #ff7ad9;
  --accent-2: #6ef3ff;
  --accent-3: #ffb347;
}

[hidden] { display: none !important; }

html,
body {
  margin: 0;
  height: 100%;
  background: #000;
  color: var(--ink);
  font: 14px/1.45 system-ui, -apple-system, "Segoe UI", sans-serif;
  overflow: hidden;
}

#stage {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}

/* ---------- panel ---------- */

.ui {
  position: fixed;
  top: 16px;
  left: 16px;
  width: min(340px, calc(100vw - 32px));
  max-height: calc(100vh - 32px);
  overflow-y: auto;
  box-sizing: border-box;
  padding: 16px;
  background: var(--glass);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--line);
  border-radius: 16px;
  transition: opacity 0.3s ease, transform 0.3s ease;
}

body.ui-hidden .ui {
  opacity: 0;
  transform: translateX(-12px);
  pointer-events: none;
}

header h1 {
  margin: 0;
  font-size: 24px;
  font-weight: 750;
  letter-spacing: 0.02em;
  background: linear-gradient(90deg, var(--accent), var(--accent-2), var(--accent-3));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.sub {
  margin: 2px 0 14px;
  color: var(--muted);
  font-size: 13px;
}

.row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}

.transport .track {
  min-width: 0;
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  color: var(--muted);
}

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.06);
  color: var(--ink);
  font: inherit;
  cursor: pointer;
  user-select: none;
  transition: background 0.2s ease, border-color 0.2s ease;
}

.btn:hover:not(:disabled) {
  background: rgba(255, 255, 255, 0.13);
  border-color: rgba(255, 255, 255, 0.25);
}

.btn:disabled {
  opacity: 0.4;
  cursor: default;
}

.btn.icon {
  width: 42px;
  height: 42px;
  padding: 0;
  font-size: 16px;
  flex: none;
}

.btn:focus-visible,
input[type="range"]:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--accent-2);
  outline-offset: 2px;
}

.corner {
  position: fixed;
  right: 16px;
  bottom: 16px;
  padding: 6px 10px;
  font-size: 12px;
  background: var(--glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

/* ---------- controls ---------- */

.controls {
  margin-top: 4px;
  border-top: 1px solid var(--line);
  padding-top: 12px;
}

.controls summary {
  cursor: pointer;
  color: var(--muted);
  font-size: 13px;
  margin-bottom: 10px;
}

.presets {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 6px;
  margin-bottom: 14px;
}

.presets .btn {
  padding: 7px 4px;
  font-size: 12px;
}

.slider {
  display: block;
  margin-bottom: 12px;
}

.slider span {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: var(--muted);
}

.slider output {
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}

input[type="range"] {
  width: 100%;
  margin: 6px 0 0;
  accent-color: var(--accent);
}

.keys {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 12px;
}

.error {
  margin: 0 0 12px;
  padding: 8px 10px;
  border-radius: 10px;
  background: rgba(255, 90, 120, 0.12);
  color: #ffb3c1;
  font-size: 13px;
}

/* ---------- start hint ---------- */

.hint {
  position: fixed;
  left: 50%;
  bottom: 12vh;
  transform: translateX(-50%);
  width: min(420px, calc(100vw - 32px));
  text-align: center;
  color: var(--muted);
  font-size: 15px;
  pointer-events: none;
  text-shadow: 0 0 12px #000;
}

/* ---------- small screens ---------- */

@media (max-width: 480px) {
  .ui {
    top: 12px;
    left: 12px;
    width: calc(100vw - 24px);
    max-height: 60vh;
  }
  .corner {
    right: 12px;
    bottom: 12px;
  }
}