body {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    margin: 0;
    background: url('background.jpg') no-repeat center center fixed;
    background-size: cover;
    font-family: Arial, sans-serif;
    color: #fff;
}

h1 {
    font-size: 2.5em;
    font-weight: bold;
    margin-bottom: 20px;
    text-shadow: 2px 2px 5px rgba(0, 0, 0, 0.7);
}

#tic-tac-toe-board {
    display: grid;
    grid-template-columns: repeat(3, 100px);
    grid-gap: 10px;
    background-color: rgba(0, 0, 0, 0.5);
    padding: 20px;
    border-radius: 10px;
}

.cell {
    width: 100px;
    height: 100px;
    background-color: rgba(255, 255, 255, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2em;
    cursor: pointer;
    border-radius: 5px;
}

#status {
    margin-top: 15px;
    font-size: 1.5em;
    font-weight: bold;
    color: #fff;
    text-shadow: 1px 1px 3px rgba(0, 0, 0, 0.7);
}

#reset-button {
    margin-top: 10px;
    padding: 10px 20px;
    font-size: 1em;
    border: none;
    background-color: #fff;
    color: #333;
    border-radius: 5px;
    cursor: pointer;
    box-shadow: 2px 2px 5px rgba(0, 0, 0, 0.5);
}

#reset-button:hover {
    background-color: #ddd;
}

#mode-button {
    margin-bottom: 15px;
    padding: 10px 20px;
    font-size: 1em;
    background-color: #fff;
    color: #333;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

#mode-button:hover {
    background-color: #ddd;
}