body {
    background-color: #121212;
    color: #ffffff;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    text-align: center;
    padding: 20px;
}

h1 {
    color: #0070f3;
    margin-bottom: 5px;
}

#status {
    font-size: 1.2rem;
    margin-bottom: 20px;
    font-weight: bold;
}

.board {
    display: grid;
    grid-template-columns: repeat(3, 100px);
    grid-template-rows: repeat(3, 100px);
    gap: 10px;
    justify-content: center;
    margin-bottom: 20px;
}

.cell {
    background-color: #1e1e1e;
    border: 2px solid #333;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.2s;
}

.cell:hover {
    background-color: #2a2a2a;
}

.cell.X { color: #0070f3; }
.cell.O { color: #ff007f; }

button {
    background-color: #0070f3;
    color: white;
    border: none;
    padding: 10px 20px;
    font-size: 1rem;
    cursor: pointer;
    border-radius: 5px;
    font-weight: bold;
}

button:hover {
    background-color: #0051b3;
}

/* Pop-up Overlay Styles */
#popup-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.85);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    transition: opacity 0.3s ease;
}

#popup-overlay.hidden {
    display: none;
}

.popup-content {
    background-color: #1e1e1e;
    padding: 30px;
    border-radius: 12px;
    border: 2px solid #333;
    text-align: center;
    box-shadow: 0px 0px 20px rgba(0, 112, 243, 0.3);
}

.popup-content h2 {
    color: #0070f3;
    margin-top: 0;
}

#winning-img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin-bottom: 15px;
    border: 1px solid #444;
}