.keypad{
    display: flex;
    flex-wrap: wrap;
    background-color: #fff;
    justify-content: center;
}

.keypad span {
    width: 33%;
    aspect-ratio: calc(6/3);
    border: 1px solid black;
    font-size: 3em;
    text-align: center;
    border-radius: 10px;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
}