body {
  font-family: Arial, sans-serif;
  background-color: #f0f0f0;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
  margin: 0;
}

#game-container {
  background-color: #fff;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  text-align: center;
}

h1 {
  margin-top: 0;
}

#sequence-display {
  font-size: 24px;
  margin: 20px 0;
}

#user-input {
  padding: 10px;
  font-size: 18px;
  width: 85%;
  margin-bottom: 10px;
}

#check-button,
#start-button {
  padding: 10px 20px;
  font-size: 16px;
  background-color: #4caf50;
  border: none;
  color: white;
  cursor: pointer;
  border-radius: 4px;
  transition: background-color 0.3s ease-in-out;
}

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

#check-button:hover,
#start-button:hover {
  background-color: #45a049;
}

#score {
  font-size: 18px;
  margin-top: 10px;
}