*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #000;
  font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Helvetica Neue', sans-serif;
  -webkit-font-smoothing: antialiased;
  -webkit-tap-highlight-color: transparent;
  -webkit-user-select: none;
  user-select: none;
  touch-action: manipulation;
}

#app {
  position: relative;
  width: 100%;
  height: 100%;
}

/* Camera feed */
#cam {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 1;
}

/* Three.js overlay */
#scene {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 2;
  touch-action: none;
}

/* Start overlay */
#start-overlay {
  position: absolute;
  inset: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.start-card {
  text-align: center;
  padding: 2rem;
  color: #fff;
}

.start-card h1 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.start-card p {
  color: rgba(255,255,255,0.6);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
}

.start-card .hint {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.35);
  margin-top: 1rem;
  margin-bottom: 0;
}

#start-btn {
  background: #4488ff;
  color: #fff;
  border: none;
  padding: 0.875rem 3rem;
  font-size: 1.1rem;
  font-weight: 600;
  border-radius: 14px;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
  letter-spacing: -0.01em;
}

#start-btn:active {
  background: #3366dd;
}

/* Bottom controls */
#controls {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 5;
  padding: 0 1rem calc(1rem + env(safe-area-inset-bottom, 0px));
  background: linear-gradient(transparent, rgba(0,0,0,0.7) 30%, rgba(0,0,0,0.85));
}

.drag-row {
  display: flex;
  align-items: center;
  height: 44px;
  margin-bottom: 6px;
  gap: 10px;
}

.axis-label {
  color: rgba(255,255,255,0.5);
  font-size: 0.85rem;
  font-weight: 600;
  width: 18px;
  text-align: center;
  flex-shrink: 0;
}

.drag-track {
  flex: 1;
  height: 36px;
  position: relative;
  display: flex;
  align-items: center;
}

.drag-fill {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  height: 3px;
  background: rgba(68,136,255,0.3);
  border-radius: 2px;
}

.drag-fill-left {
  right: 50%;
  left: 0;
}

.drag-fill-right {
  left: 50%;
  right: 0;
}

.drag-thumb {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 28px;
  height: 28px;
  background: #4488ff;
  border-radius: 50%;
  box-shadow: 0 2px 8px rgba(0,0,0,0.4);
  z-index: 2;
  transition: transform 0.05s ease-out;
}

.drag-thumb:active {
  transform: translate(-50%, -50%) scale(1.2);
}

.axis-val {
  color: #fff;
  font-size: 1rem;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  width: 32px;
  text-align: right;
  flex-shrink: 0;
}

.axis-unit {
  color: rgba(255,255,255,0.4);
  font-size: 0.75rem;
  flex-shrink: 0;
}

/* Volume display */
#volume-row {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 4px;
  margin-top: 4px;
  padding-top: 6px;
  border-top: 1px solid rgba(255,255,255,0.08);
}

#volume-val {
  color: #fff;
  font-size: 1.4rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
}

#volume-unit {
  color: rgba(255,255,255,0.4);
  font-size: 0.8rem;
  font-weight: 500;
}

/* Hint */
#hint {
  position: absolute;
  bottom: calc(210px + env(safe-area-inset-bottom, 0px));
  left: 50%;
  transform: translateX(-50%);
  z-index: 5;
  color: rgba(255,255,255,0.45);
  font-size: 0.75rem;
  text-align: center;
  padding: 0.35rem 0.75rem;
  background: rgba(0,0,0,0.5);
  border-radius: 20px;
  pointer-events: none;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

/* Hidden state */
.hidden {
  display: none !important;
}