.numpad {
    width: 100%;
    height: 200px;
    display: flex;
    flex-flow: row wrap;
}

.numpad span {
    display: flex;
    align-items: center;
    justify-content: center;
    flex: 32.3333%;
    border: 1px solid #D8D8D8;
}

.numpad span:nth-child(2n){
    border-right: 0;
}

.numpad span:nth-child(-n + 9){
    border-bottom: 0;
}

.numpad span:nth-child(odd){
    border-right: 0;
}

.numpad span:nth-child(3n){
    border-right: 1px solid #D8D8D8;
}