body {
  font-family: system-ui, sans-serif;
  background-color: #f8f9fa;
  margin: 0;
  padding: 0;
  text-align: center;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 1rem;
  box-sizing: border-box;
}

h1 {
  text-align: center;
  margin-bottom: 1rem;
}

#game-canvas, #scoreChart {
  width: 100%;
  height: auto;
  display: block;
  margin: 0 auto 0.5rem;
}

#game-area > div.grid {
  display: grid;
  position: relative;
  max-width: 480px;
  aspect-ratio: 1 / 1;
  margin: 0 auto;
  gap: 6px;
  padding: 4px;
  place-items: center;
}
  max-width: 480px;
  aspect-ratio: 1 / 1;
  margin: 0 auto;
  display: grid;
  gap: 6px;
  padding: 4px;
}

.button-bar {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin: 1rem 0;
}

.button-bar button {
  font-size: 1rem;
  padding: 8px 16px;
  border: 1px solid #999;
  cursor: pointer;
}

#start-btn {
  background-color: #d4edda;
  border-color: #b7dfc3;
}

#start-btn:hover {
  background-color: #c3e6cb;
}

#restart-btn {
  background-color: #f8d7da;
  border-color: #f5c6cb;
}

#restart-btn:hover {
  background-color: #f1b0b7;
}

#submit-btn {
  background-color: #e0e0e0;
  border-color: #ccc;
}

#submit-btn:hover {
  background-color: #d0d0d0;
}

button:disabled {
  background-color: #ccc;
  color: #666;
  cursor: not-allowed;
}

.correct {
  border: 2px solid #28a745;
  box-shadow: 0 0 4px #28a745;
}

.wrong {
  border: 2px solid #dc3545;
  box-shadow: 0 0 4px #dc3545;
}

.missed {
  border: 2px solid #ffc107;
  box-shadow: 0 0 4px #ffc107;
}

#scoreboard {
  max-width: 480px;
  margin: 0.5rem auto;
  padding: 0.5rem;
  background-color: #f4f4f4;
  border: 1px solid #ccc;
  font-size: 1.1rem;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.5rem;
  justify-items: center;
}

.color-red { color: #e74c3c; }
.color-blue { color: #3498db; }
.color-green { color: #2ecc71; }
.color-yellow { color: #f1c40f; }
.color-orange { color: #e67e22; }
.color-purple { color: #9b59b6; }
.color-pink { color: #ff69b4; }
.color-cyan { color: #00bcd4; }
.color-grey { color: #95a5a6; }
.color-brown { color: #8d6e63; }

.flash {
  animation: flash-reset 0.3s ease-in-out;
}

@keyframes flash-reset {
  0% { background-color: #fff; }
  50% { background-color: #cce5ff; }
  100% { background-color: #fff; }
}

@media (max-width: 500px) {
  .button-bar {
    flex-direction: column;
    align-items: center;
  }

  .button-bar button {
    width: 100%;
    max-width: 200px;
    font-size: 0.95rem;
    padding: 10px 20px;
  }

  #scoreboard {
    font-size: 0.95rem;
    padding: 0.75rem;
  }
}