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

body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  background: linear-gradient(135deg, #f3f4f6, #e2e8f0);
  font-family: 'Arial', sans-serif;
}

#app {
  text-align: center;
  background: white;
  border-radius: 15px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
  padding: 20px;
}

h1 {
  margin-bottom: 20px;
  color: #333;
}

.buttons {
  display: flex;
  gap: 20px;
  justify-content: center;
}

button {
  padding: 10px 20px;
  font-size: 1.5rem;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  background: linear-gradient(135deg, #6a82fb, #fc5c7d);
  color: white;
  transition: background 0.3s, transform 0.3s;
}

button:hover {
  background: linear-gradient(135deg, #fc5c7d, #6a82fb);
  transform: translateY(-3px);
}

.hidden {
  display: none;
}

#board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-top: 20px;
}

.cell {
  width: 80px;
  height: 80px;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 3rem;
  background-color: #e2e8f0;
  border: 2px solid #4a5568;
  border-radius: 10px;
  cursor: pointer;
  transition: background-color 0.3s, transform 0.3s;
}

.cell:hover {
  background-color: #cbd5e1;
  transform: scale(1.05);
}

.cell.X {
  color: #6a82fb; /* Color for X */
}

.cell.O {
  color: #fc5c7d; /* Color for O */
}