body {
  font-family: 'Segoe UI', sans-serif;
  margin: 0;
  background: #f0f4f8;
  color: #333;
}

header {
  background: #021024;
  color: #fff;
  text-align: center;
  padding: 2rem;
}

h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.grid-intro {
  padding: 2rem;
}

.grid-board {
  display: grid;
  grid-template-columns: repeat(4, 80px);
  gap: 10px;
  margin-top: 1rem;
}

.cell {
  background: #5a6e7f;
  color: #fff;
  padding: 1rem;
  text-align: center;
  border-radius: 6px;
}

.leaderboard {
  background: #e4edf3;
  padding: 2rem;
}

footer {
  background: #021024;
  color: #fff;
  text-align: center;
  padding: 1rem;
}