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

#game {
  text-align: center;
  padding: 10px;
}

#guide-container {
  margin-bottom: 10px;
  text-align: center;
}

#guide-image {
  width: 150px;
  opacity: 0.8;
  border: 2px solid #ddd;
  border-radius: 5px;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

#puzzle-container {
  display: grid;
  grid-template-columns: repeat(3, 100px);
  grid-gap: 5px;
  margin: 20px auto;
  width: 100%;
  max-width: 310px;
  height: 310px;
  min-width: 300px;
  min-height: 300px;
  background-color: #ddd;
  position: relative;
}

.piece {
  width: 100px;
  height: 100px;
  cursor: pointer;
  border: 1px solid #fff;
  box-sizing: border-box;
  user-select: none;
}

#fullscreen-message {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  background: linear-gradient(135deg, #ff7eb3, #ff758c);
  color: white;
  font-family: 'Arial', sans-serif;
  font-size: 2.5rem;
  text-align: center;
  padding: 20px;
  animation: fadeIn 1s ease-in-out;
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}