/* Container styling */
#tuner {
  text-align: center;
  font-family: "Segoe UI", sans-serif;
  background: linear-gradient(145deg, #f3f4f6, #ffffff);
  padding: 30px;
  max-width: 350px;
  margin: 30px auto;
  border-radius: 15px;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

/* Title */
#tuner h2 {
  font-size: 1.5rem;
  margin-bottom: 20px;
  color: #333;
}

/* Start button */
#start-tuner {
  background-color: #4caf50;
  color: white;
  padding: 12px 25px;
  font-size: 1rem;
  border: none;
  border-radius: 25px;
  cursor: pointer;
  transition: background-color 0.3s, transform 0.2s;
}
#start-tuner:hover {
  background-color: #45a049;
  transform: scale(1.05);
}
#start-tuner:active {
  transform: scale(0.98);
}

/* Stop button */
#stop-tuner {
  background-color: #e53935;
  color: white;
  padding: 12px 25px;
  font-size: 1rem;
  border: none;
  border-radius: 25px;
  cursor: pointer;
  transition: background-color 0.3s, transform 0.2s;
  margin-left: 10px;
}
#stop-tuner:hover {
  background-color: #c62828;
  transform: scale(1.05);
}
#stop-tuner:active {
  transform: scale(0.98);
}

/* Note display */
#note {
  font-size: 64px;
  font-weight: bold;
  margin-top: 20px;
  color: #222;
}

/* Frequency display */
#frequency {
  font-size: 20px;
  margin-top: 10px;
  color: #555;
}

#meter {
  position: relative;
  width: 200px;
  height: 100px;
  margin: 30px auto 0;
}

/* Arc background - thick curved arc using CSS */
#arc {
  width: 200px;
  height: 100px;
  position: absolute;
  top: 0;
  left: 0;
}

/* Create the curved arc using CSS */
#arc::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 200px;
  height: 100px;
  border: 8px solid #d1d5db; /* thick light gray arc */
  border-radius: 200px 200px 0 0; /* curved top, flat bottom */
  border-bottom: none;
  background: transparent;
}

/* Markers - clean and minimal */
.marker {
  position: absolute;
  background: #d1d5db; /* light gray to match arc */
  top: 1px; /* Position at the very top edge of the arc */
  left: 50%;
  transform-origin: center 100px; /* pivot around arc center, adjusted for proper positioning */
}

/* Center marker - thicker and longer */
.marker.center {
  width: 6px;
  height: 20px;
  background: #d1d5db;
}

/* Side markers - thinner and shorter, positioned along the arc */
.marker.side-left {
  width: 2px;
  height: 14px;
  background: #d1d5db;
  transform: rotate(-25deg);
}

.marker.side-right {
  width: 2px;
  height: 14px;
  background: #d1d5db;
  transform: rotate(25deg);
}

/* Red pointer/needle - thick and prominent */
#arc-needle {
  width: 4px; /* thick needle */
  height: 70px;
  background: #ef4444; /* vibrant red */
  position: absolute;
  bottom: 0;
  left: 50%;
  transform-origin: bottom center;
  transform: rotate(0deg);
  transition: transform 0.1s ease-out;
  border-radius: 3px;
  box-shadow: 0 0 6px rgba(239, 68, 68, 0.4);
}

/* Responsive */
@media (max-width: 400px) {
  #tuner {
    max-width: 90%;
    padding: 20px;
  }
}