body {
  font-family: Arial, sans-serif;
  background-color: #f5f5f5;
  margin: 0;
  padding: 0;
}

.container {
  max-width: 800px;
  margin: 40px auto;
  background-color: #fff;
  padding: 20px;
  box-shadow: 0 0 15px rgba(0, 0, 0, 0.1);
}

h1 {
  text-align: center;
  color: #333;
}

label, p {
  font-size: 16px;
}

select, button {
  margin: 10px 5px;
  padding: 10px;
  font-size: 14px;
}

button {
  background-color: #007acc;
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
}

button:disabled {
  background-color: #ccc;
  cursor: not-allowed;
}

button:hover:enabled {
  background-color: #005fa3;
}

#result {
  font-weight: bold;
  margin-top: 20px;
}

#explanation {
  margin-top: 30px;
}