body {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    justify-content: center;
    margin: 0;
    padding: 0;
    background-color: #80331c

}

#calculator {
    display: flex;
    flex-direction: column;
    width: 300px;
    height: 500px;
    margin: 0 auto;
    align-items: center;
    justify-content: center;
    background-color: #333;
    padding: 10px;
    border: 5px outset #6f6462;
    border-radius: 8px;
}

#display {

    width: 100%;
    background-color: #222;
    color: white;
    text-align: right;
    padding: 10px 0;
    margin-bottom: 30px;
    font-size: 30px;
    border: 1px solid #ddd;
    border-radius: 4px;
    overflow: hidden;
}

span {
    padding-right: 3px;
}

button {
    height: 75px;
    flex: 25%;
    margin: 2px;
    padding: 15px;
    font-size: 28px;
    border: 1px solid #6b6565;
    background-color: #f1f1f1;
    cursor: pointer;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
} 

/* #multiply {
    padding-top: 28px;
} */

.digit:active {
    opacity: 0.75;
}

.row {
    display: flex;
    width: 100%;
    flex-direction: row;
    align-items: center;
    justify-content:center;
}

/* not exact? */
/* #zero {
    flex: 52.5%; 
} */

.operator,
#equals {
    background-color: #cf542f;

}

/* .operator:active {
    opacity: 0.75;
} */

#equals:active {
    opacity: 0.75;
}

#clear,
#sign,
#percent {
    background-color: #4765b7;
}
#delete:active,
#clear:active,
#sign:active,
#percent:active {
    opacity: 0.75;
}

/* #decimal {
    font-size: 30px;
} */