*,
*::before,
*::after {
    box-sizing: border-box;
    font-weight: normal;
}

body {
    margin: 0;
    padding: 0;
    background: linear-gradient(to right, #CBCE91FF, #EA738DFF);
    display: flex;
    justify-content: center;
}

button:active {
    transform: translateY(4px);
}

.calculator-grid {
    display: grid;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    grid-template-columns: repeat(4, 100px);
    grid-template-rows: minmax(120px, auto) repeat(5, 100px);
    min-width: fit-content;
    border: #37374a 1px solid;
    margin: 5px;
    -webkit-box-shadow: 10px 10px 5px 0 rgba(0, 0, 0, 0.75);
    -moz-box-shadow: 10px 10px 5px 0 rgba(0, 0, 0, 0.75);
    box-shadow: 10px 10px 5px 0 rgba(0, 0, 0, 0.75);
    border-radius: 7px;
    padding: 8px;
}

.calculator-grid>button {
    cursor: pointer;
    font-size: 2rem;
    outline: 0;
    background-color: #E7EAEFA1;
    border-radius: 25px;
    border: none;
    margin: 3px;
}

.calculator-grid>button:hover {
    background-color: #a9a9a9;
}

.span-two {
    grid-column: span 2;
    color: #f80225;
    background-color: rgba(226, 177, 40, 0.8);
    border-radius: 7px;
}

.output {
    grid-column: 1 / -1;
    background-color: rgba(0, 0, 0, 0.75);
    display: flex;
    align-items: flex-end;
    justify-content: space-around;
    flex-direction: column;
    padding: 10px;
    word-wrap: break-word;
    word-break: break-all;
    width: 100%;
    min-height: 68px;
    border-radius: 3px;
}

.output .previous-operand {
    color: rgba(255, 255, 255, 0.75);
    font-size: 1.5rem;
}

.output .current-operand {
    color: white;
    font-size: 2.5rem;
}


@media screen and (max-width: 456px) {
    .calculator-grid > button {
        font-size: 21px;

    }

    .calculator-grid {
        width: 94%;
        grid-template-columns: repeat(4, 25%);
    }
}