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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background-color: #f5f5f7;
}

.container {
  text-align: center;
  background: white;
  padding: 2rem;
  border-radius: 20px;
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

h1 {
  color: #1d1d1f;
  margin-bottom: 1.5rem;
}

.game-status {
  margin-bottom: 1.5rem;
  font-size: 1.2rem;
  color: #1d1d1f;
}

.game-board {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 8px;
  background: #e0e0e0;
  padding: 10px;
  border-radius: 10px;
  margin-bottom: 1.5rem;
}

.cell {
  width: 50px;
  height: 50px;
  background: white;
  border-radius: 50%;
  cursor: pointer;
  transition: background-color 0.3s;
}

.cell.red {
  background: #ff3b30;
}

.cell.yellow {
  background: #ffcc00;
}

.restart-btn {
  background: #007aff;
  color: white;
  border: none;
  padding: 12px 24px;
  border-radius: 20px;
  font-size: 1rem;
  cursor: pointer;
  transition: background-color 0.3s;
}

.restart-btn:hover {
  background: #0066d6;
}