/* ambient sound widget */
#ambient-widget {
  position: fixed;
  bottom: 24px;
  left: 24px;
  z-index: 90;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 12px;
  font-family: 'Syne', sans-serif;
}

#ambient-toggle {
  background: linear-gradient(135deg, rgba(var(--accent-rgb), 0.18), rgba(var(--easy-rgb), 0.10));
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(var(--accent-rgb), 0.35);
  border-radius: 30px;
  color: var(--text);
  font-weight: 700;
  font-size: 14px;
  display: flex;
  align-items: center;
  cursor: pointer;
  transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
  box-shadow: 0 4px 16px var(--shadow-sm), 0 0 12px rgba(var(--accent-rgb), 0.15);

  width: 44px;
  height: 44px;
  padding: 0;
  overflow: hidden;
  white-space: nowrap;
}

#ambient-toggle:hover {
  width: 138px;
  border-color: rgba(var(--accent-rgb), 0.5);
  box-shadow: 0 8px 24px var(--shadow-md), 0 0 20px rgba(var(--accent-rgb), 0.25);
}

.ambient-toggle-icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.ambient-toggle-text {
  opacity: 0;
  transform: translateX(-8px);
  transition: all 0.3s ease;
}

#ambient-toggle:hover .ambient-toggle-text {
  opacity: 1;
  transform: translateX(0);
  transition-delay: 0.05s;
}

#ambient-toggle.active-glow {
  border-color: var(--accent);
  background: rgba(var(--accent-rgb), 0.15);
  box-shadow: 0 0 15px rgba(var(--accent-rgb), 0.3);
  color: var(--text);
}

#ambient-panel {
  background: var(--surface-blur);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  box-shadow: 0 10px 30px var(--shadow-lg);
  opacity: 0;
  transform: translateY(10px) scale(0.95);
  pointer-events: none;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  transform-origin: bottom left;
  min-width: 220px;
}

#ambient-panel.open {
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: auto;
}

.ambient-tracks {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}

.ambient-btn {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 12px;
  width: 100%;
  aspect-ratio: 1/1;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  cursor: pointer;
  transition: all 0.2s ease;
  color: var(--text-dim);
}

.ambient-btn:hover {
  background: var(--surface3);
  transform: translateY(-2px);
  color: var(--text);
}

.ambient-btn.loading {
  pointer-events: none;
  opacity: 0.6;
  position: relative;
}
.ambient-btn.loading::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 12px;
  border: 2px solid transparent;
  border-top-color: var(--accent);
  animation: ambient-spin 0.7s linear infinite;
}
@keyframes ambient-spin {
  to { transform: rotate(360deg); }
}

.ambient-btn.playing {
  background: rgba(var(--easy-rgb), 0.15);
  border-color: var(--easy);
  color: var(--easy);
  animation: pulse-border 2s infinite ease-in-out;
}

@keyframes pulse-border {
  0% { box-shadow: 0 0 0 0 rgba(var(--easy-rgb), 0.4); }
  70% { box-shadow: 0 0 0 8px rgba(var(--easy-rgb), 0); }
  100% { box-shadow: 0 0 0 0 rgba(var(--easy-rgb), 0); }
}

.ambient-volume {
  display: flex;
  align-items: center;
  gap: 12px;
}

.ambient-volume span {
  font-size: 16px;
  color: var(--text-muted);
}

.ambient-volume input[type="range"] {
  flex: 1;
  appearance: none;
  -webkit-appearance: none;
  background: transparent;
  height: 24px;
}

.ambient-volume input[type="range"]::-webkit-slider-runnable-track {
  width: 100%;
  height: 4px;
  background: var(--border);
  border-radius: 2px;
}

.ambient-volume input[type="range"]::-webkit-slider-thumb {
  appearance: none;
  -webkit-appearance: none;
  height: 16px;
  width: 16px;
  border-radius: 50%;
  background: var(--text);
  margin-top: -6px;
  cursor: pointer;
  box-shadow: 0 2px 4px var(--shadow-sm);
  transition: transform 0.1s;
}

.ambient-volume input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

.ambient-volume input[type="range"]:focus {
  outline: none;
}

/* volume label */
.ambient-vol-label {
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  width: 28px;
  flex-shrink: 0;
  text-align: right;
  color: var(--text-muted);
  transition: color 0.2s;
}
.ambient-vol-label.boosted {
  color: var(--accent);
  text-shadow: 0 0 8px rgba(var(--accent-rgb), 0.4);
}

/* slider track glow when boosted */
.ambient-volume input[type="range"].boosted::-webkit-slider-runnable-track {
  background: linear-gradient(90deg, var(--border) 0%, rgba(var(--accent-rgb), 0.5) 100%);
}
.ambient-volume input[type="range"].boosted::-webkit-slider-thumb {
  background: var(--accent);
  box-shadow: 0 0 8px rgba(var(--accent-rgb), 0.5);
}

/* responsive */
@media (max-width: 768px) {
  #ambient-widget { bottom: 16px; left: 16px; }
  #ambient-panel { min-width: 200px; padding: 12px; }
  .ambient-btn { font-size: 20px; }
}