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

body {
  background-color: #1a1a2e;
  color: white;
  font-family: 'Segoe UI', sans-serif;
  text-align: center;
  padding: 40px 20px;
  min-height: 100vh;
}

h1 {
  font-size: 2rem;
  letter-spacing: 0.1em;
  margin-bottom: 20px;
  color: #e94560;
}

#stats {
  display: flex;
  justify-content: center;
  gap: 40px;
  font-size: 1rem;
  margin-bottom: 24px;
  color: #aaa;
}

#stats strong {
  color: white;
  font-size: 1.2rem;
}

#board {
  display: grid;
  grid-template-columns: repeat(4, 100px);
  gap: 6px;
  margin: 0 auto 24px;
  width: fit-content;
}

.cell {
  width: 100px;
  height: 100px;
  background-color: #16213e;
  border: 2px solid #0f3460;
  font-size: 2rem;
  font-weight: bold;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border-radius: 8px;
  transition: background-color 0.1s, transform 0.1s;
  user-select: none;
}

.cell:hover {
  background-color: #0f3460;
  transform: scale(1.05);
}

.empty {
  background-color: #0f0f1a;
  border: 2px solid #222;
  cursor: default;
}

.empty:hover {
  background-color: #0f0f1a;
  transform: none;
}

#shuffleBtn {
  padding: 12px 40px;
  font-size: 1rem;
  background-color: #e94560;
  color: white;
  border: none;
  cursor: pointer;
  border-radius: 6px;
  letter-spacing: 0.05em;
  transition: background-color 0.2s;
}

#shuffleBtn:hover {
  background-color: #c73652;
}