* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: Arial, sans-serif;
  background-color: #f5f5f5;
  display: flex;
  flex-direction: column;
  align-items: center;
  min-height: 100vh;
  color: #333;
}

header {
  width: 100%;
  background-color: #4CAF50;
  color: white;
  padding: 20px;
  text-align: center;
  display: flex;
  justify-content: space-around;
  align-items: center;
}

h1 {
  margin: 0;
}

.score-container {
  font-size: 1.5rem;
  font-weight: bold;
}

main {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  padding: 20px;
}

.game-container {
  background-color: white;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
  max-width: 600px;
  width: 100%;
}

#game-canvas {
  background-color: #e0e0e0;
  display: block;
  margin: 0 auto;
  border: 2px solid #333;
}

.controls {
  display: flex;
  justify-content: center;
  margin: 20px 0;
}

button {
  padding: 10px 20px;
  margin: 0 10px;
  background-color: #4CAF50;
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 1rem;
  transition: background-color 0.3s;
}

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

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

.instructions {
  margin-top: 20px;
  text-align: center;
  padding: 10px;
  border-top: 1px solid #ddd;
}

.instructions h3 {
  margin-bottom: 10px;
}

.instructions p {
  margin: 5px 0;
  font-size: 0.9rem;
}

footer {
  width: 100%;
  background-color: #ddd;
  padding: 15px;
  text-align: center;
  margin-top: 20px;
}

.back-link {
  display: inline-block;
  margin: 10px 0;
  color: #4CAF50;
  text-decoration: none;
  font-weight: bold;
}

.back-link:hover {
  text-decoration: underline;
}

@media (max-width: 600px) {
  #game-canvas {
    width: 100%;
    height: auto;
  }
  
  .controls {
    flex-direction: column;
    align-items: center;
  }
  
  button {
    margin: 5px 0;
    width: 80%;
  }
}