body {
    font-size: 20px;
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    overflow: hidden;
    display: flex;
    justify-content: center;
    algin-items: center;
}

#wrapper {
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
}

#calculator {
    display: grid;
    gap: 5px;
    grid-auto-columns: minmax(0, 1fr);
    grid-auto-flow: column;
    padding: 20px;
    border: 1px solid #3f3f3f;
    border-radius: 5px;
}

#display {
    grid-row: 1;
    grid-column: 1/5;
    text-align: right;
    border: 2px solid black;
    border-radius: 5px;
    padding: 0 5px;
    background-color: #d7d7d7;
}

#ac {
    grid-row: 2;
    grid-column: 1;
}

#c {
    grid-row: 2;
    grid-column: 2;
}

#plusminus {
    grid-row: 2;
    grid-column: 3;
}

#divide {
    grid-row: 2;
    grid-column: 4;
}

#k7 {
    grid-row: 3;
    grid-column: 1;
}

#k8 {
    grid-row: 3;
    grid-column: 2;
}

#k9 {
    grid-row: 3;
    grid-column: 3;
}

#multiply {
    grid-row: 3;
    grid-column: 4;
}

#k4 {
    grid-row: 4;
    grid-column: 1;
}

#k5 {
    grid-row: 4;
    grid-column: 2;
}

#k6 {
    grid-row: 4;
    grid-column: 3;
}

#subtract {
    grid-row: 4;
    grid-column: 4;
}

#k1 {
    grid-row: 5;
    grid-column: 1;
}

#k2 {
    grid-row: 5;
    grid-column: 2;
}

#k3 {
    grid-row: 5;
    grid-column: 3;
}

#addition {
    grid-row: 5;
    grid-column: 4;
}

#k0 {
    grid-row: 6;
    grid-column: 1/3;
}

#period {
    grid-row: 6;
    grid-column: 3;
}

#equals {
    grid-row: 6;
    grid-column: 4;
}