body {
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

#container {
    display: grid;
    height: 600px;
    width: 600px;
    border-radius: 15px;
    background: #e1e1e1;
    padding: 3px;

    grid-template-columns: repeat(10, calc(600px/10));
    grid-template-rows: repeat(10, calc(600px/10));
}



.tile {
    background: #f4f4f4;
    margin: 3px;
    border-radius: 10px;
    transition: 200ms ease-in-out;
}
.tile:hover {
    background: #e4e4e4;
}