body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f0f2f5;
    color: #333;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
}

.game-container {
    background: white;
    padding: 40px;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    text-align: center;
    max-width: 400px;
    width: 100%;
}

.header {
    margin-bottom: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 2px solid #eee;
    padding-bottom: 10px;
}

h1 {
    color: #2c3e50;
    margin: 0;
}

.back-link {
    text-decoration: none;
    color: #666;
    font-size: 0.9rem;
    border: 1px solid #ccc;
    padding: 5px 10px;
    border-radius: 4px;
}

.back-link:hover {
    background-color: #f0f0f0;
}

.status {
    font-size: 1.2rem;
    margin-bottom: 20px;
    font-weight: bold;
    color: #2c3e50;
    height: 1.5em;
}

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

.cell {
    width: 100px;
    height: 100px;
    background-color: #f8f9fa;
    border: 2px solid #e9ecef;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.2s ease;
}

.cell:hover {
    background-color: #e9ecef;
}

.cell.x {
    color: #e74c3c;
}

.cell.o {
    color: #3498db;
}

#restart-btn {
    padding: 10px 20px;
    font-size: 1rem;
    cursor: pointer;
    background-color: #2ecc71;
    color: white;
    border: none;
    border-radius: 5px;
    transition: background-color 0.2s;
}

#restart-btn:hover {
    background-color: #27ae60;
}