body {
  background: #222;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
  font-family: 'Arial', sans-serif;
}

#gameCanvas {
  background: #fff;
  border: 2px solid #333;
  box-shadow: 0 0 20px #0008;
  display: none; /* 初期状態では非表示 */
}

.start-screen {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 30px;
  border-radius: 20px;
  text-align: center;
  box-shadow: 0 10px 30px rgba(0,0,0,0.3);
  max-width: 800px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
}

.start-screen h1 {
  font-size: 2.5em;
  margin-bottom: 8px;
  text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.subtitle {
  font-size: 1.2em;
  margin-bottom: 20px;
  opacity: 0.9;
}

.instructions {
  background: rgba(255,255,255,0.1);
  padding: 15px;
  border-radius: 15px;
  margin: 10px 0;
  text-align: left;
}

.instructions h2 {
  color: #ffd700;
  margin-bottom: 8px;
  font-size: 1.2em;
}

.instructions ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.instructions li {
  margin: 3px 0;
  padding: 3px 0;
  border-bottom: 1px solid rgba(255,255,255,0.2);
  font-size: 0.95em;
  line-height: 1.2;
}

.instructions li:last-child {
  border-bottom: none;
}

.instructions strong {
  color: #ffd700;
}

.ranking-section {
  background: rgba(255,255,255,0.1);
  padding: 15px;
  border-radius: 15px;
  margin: 10px 0;
  text-align: left;
}

.ranking-container {
  display: flex;
  gap: 20px;
  justify-content: space-between;
}

.ranking-column {
  flex: 1;
}

.ranking-column h3 {
  color: #ffd700;
  margin-bottom: 10px;
  font-size: 1.1em;
  text-align: center;
}

.ranking-list {
  max-height: 250px;
  overflow-y: auto;
}

.ranking-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 6px 0;
  border-bottom: 1px solid rgba(255,255,255,0.2);
  font-size: 0.9em;
  height: 20px;
  line-height: 1;
}

.ranking-item:last-child {
  border-bottom: none;
}

.ranking-item.header {
  font-weight: bold;
  color: #ffd700;
  border-bottom: 2px solid #ffd700;
  font-size: 0.95em;
  height: 24px;
}

.ranking-item .rank {
  width: 40px;
  text-align: center;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.ranking-item .name,
.ranking-item .date {
  flex: 1;
  text-align: left;
  margin: 0 8px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.ranking-item .score {
  width: 120px;
  text-align: right;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-family: 'Courier New', monospace;
  font-weight: bold;
}

.start-controls {
  margin-top: 20px;
}

.start-button {
  background: linear-gradient(45deg, #ff6b6b, #ee5a24);
  color: white;
  border: none;
  padding: 15px 40px;
  font-size: 1.2em;
  border-radius: 50px;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 5px 15px rgba(0,0,0,0.2);
  margin-bottom: 8px;
}

.start-button:hover {
  transform: translateY(-2px);
  box-shadow: 0 7px 20px rgba(0,0,0,0.3);
  background: linear-gradient(45deg, #ff5252, #d63031);
}

.start-button:active {
  transform: translateY(0);
}

.start-hint {
  font-size: 0.85em;
  opacity: 0.8;
  margin: 0;
}