body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  text-align: center;
  margin: 20px;
  background: #fff0f4;
  color: #6b0b0b;
}

.brand-header {
  font-weight: 900;
  font-size: 2.5rem;
  color: #d81e5b;
  margin-bottom: 10px;
  font-family: 'Arial Black', Gadget, sans-serif;
}

h1 {
  margin-top: 0;
  color: #ad1457;
}

#strings {
  display: flex;
  justify-content: center;
  margin: 20px 0;
  gap: 15px;
}

.string-bar {
  padding: 15px 25px;
  background-color: #f8bbd0;
  border-radius: 25px;
  font-weight: 700;
  font-size: 1.2rem;
  color: #6b0b0b;
  cursor: default;
  transition: background-color 0.3s ease, color 0.3s ease;
  user-select: none;
  min-width: 110px;
}

.string-bar.active {
  background-color: #d81e5b;
  color: white;
  box-shadow: 0 0 15px rgba(216, 30, 91, 0.8);
}

#note {
  font-size: 6rem;
  margin: 20px 0 0 0;
  font-weight: 700;
  color: #b71c46;
}

#detectedFreq {
  font-size: 2rem;
  margin: 10px 0;
  color: #880e4f;
}

#tuningStatus {
  font-size: 1.5rem;
  margin: 10px 0 30px 0;
  font-weight: 600;
}

#tuningStatus.in-tune {
  color: #d81e5b;
}

#tuningStatus.tune-up {
  color: #ad1457;
}

#tuningStatus.tune-down {
  color: #880e4f;
}

button {
  font-size: 1rem;
  margin: 10px 15px;
  padding: 12px 30px;
  border-radius: 30px;
  border: none;
  cursor: pointer;
  background-color: #d81e5b;
  color: white;
  transition: background-color 0.3s ease;
  font-weight: 700;
  box-shadow: 0 4px 6px rgba(216, 30, 91, 0.5);
}

button:disabled {
  background-color: #f48fb1;
  cursor: not-allowed;
  box-shadow: none;
}

button:hover:not(:disabled) {
  background-color: #ad1457;
}