body {
    font-family: Arial, sans-serif;
}

#grid-container {
    display: grid;
    grid-template-columns: repeat(4, 100px);
    grid-template-rows: repeat(4, 100px);
    gap: 10px;
}

.tile {
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #ccc;
    font-size: 24px;
    font-weight: bold;
}