div {
    border: 3px solid black;
    width: 45%;
    height: 100%;
    display: inline-block;
    float: left;
    text-align: center;
    font-weight: 900;
    font-size: xx-large;
}

.kodilla {
    background: #28a745;
}

.checkers {
    background: #b1b1b1;
}

a {
    color: black;
    text-decoration: none;
}