body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    display: flex;
    justify-content: center;
    text-align: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background: linear-gradient(45deg, #1e79b7, #bad0e6);
    color: rgba(255, 255, 255, 0.8);
}

#board {
    display: grid;
    grid-template-columns: repeat(3, 100px);
    grid-gap: 10px;
    margin-bottom: 20px;
}

.cell {
    width: 100px;
    height: 100px;
    border: 2px solid #0a5281;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 36px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.cell:hover {
    background-color: #2980b9;
}

.message {
    text-align: center;
    font-size: 20px;
    margin-bottom: 20px;
    padding: 10px;
    border-radius: 5px;
    background: rgba(255, 255, 255, 0.2);
}