body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #0f172a;
  color: white;
}

/* center everything */
.container {
  height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 40px;
}

/* play button */
#playBtn {
  font-size: 2rem;
  padding: 30px 50px;
  border: none;
  border-radius: 12px;
  background: #2563eb;
  color: white;
  cursor: pointer;
  transition: transform 0.1s, background 0.15s;
}

#playBtn:hover {
  background: #3b82f6;
}

#playBtn:active {
  transform: scale(0.95);
}

#debugText {
  min-height: 60px;
  padding: 16px;
  width: 300px;
  text-align: center;

  background: #1f2937;
  border: 1px solid #374151;
  border-radius: 8px;

  color: #e5e7eb;
  font-size: 1.1rem;
  white-space: pre-wrap;
}

/* slider */
.sliderGroup {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.sliderGroup label {
  font-size: 0.9rem;
  color: #9ca3af;
}

#volumeSlider {
  width: 200px;
}