.number-output {
  display: block;
}

.avg-row {
  font-weight: bold;
  background-color: #f8f9fa;
  padding: 10px;
  border-top: 2px solid #ccc;
}

.btn-group > .btn {
  min-width: 45px;
}

.error-message {
  color: red;
  font-size: 0.85em;
  display: none;
}