body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  background: #f5f5f5;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100vh;
}

.container {
  background: #ffffff;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  text-align: center;
  max-width: 400px;
  width: 90%;
}

h1 {
  margin-bottom: 1rem;
}

p {
  margin-bottom: 1.5rem;
  color: #333;
}

.message {
  font-size: 1.1rem;
  font-style: bold;
}

.input-group {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.input-group input {
  width: 40px;
  height: 40px;
  text-align: center;
  font-size: 1.2rem;
  border: 2px solid #ccc;
  border-radius: 4px;
  outline: none;
}

.input-group input:focus {
  border-color: #007bff;
}

.feedback-group {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

/* Cuadros de retroalimentación */
.feedback-box {
  width: 40px;
  height: 40px;
  border-radius: 4px;
  border: 2px solid #ccc;
}

/* Ejemplo: todas en verde para la demo */
.correct {
  background-color: #28a745; /* Verde */
  border-color: #28a745;
}

button {
  background-color: #007bff;
  color: #fff;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 4px;
  font-size: 1rem;
  cursor: pointer;
  margin-bottom: 1rem;
}

button:hover {
  background-color: #0056b3;
}

.legend {
  text-align: left;
  margin-top: 1rem;
}

.legend-item {
  display: flex;
  align-items: center;
  margin-bottom: 0.5rem;
}

.legend-color {
  width: 20px;
  height: 20px;
  margin-right: 0.5rem;
  border-radius: 4px;
  border: 2px solid #ccc;
}

.null {
  background-color: #e8e8e8; /* Correcto en posición */
  border-color: #636363;
}

.green {
  background-color: #28a745; /* Correcto en posición */
  border-color: #28a745;
}

.yellow {
  background-color: #ffc107; /* Correcto en otra posición */
  border-color: #ffc107;
}

.red {
  background-color: #dc3545; /* Incorrecto */
  border-color: #dc3545;
}

.warning {
  background-color: #ff5100;
  color: #fff;
  border-color: #ff5100;
}

.hidden {
  display: none;
}