*,
*::before,
*::after {
    box-sizing: border-box;
    font-family: "Poppins", sans-serif;
    font-weight: 500;
    font-style: normal;
}

body{
    margin: 0;
    padding: 0;
    background: linear-gradient(to right, rgb(255, 159, 68), rgb(252, 77, 77));
}
.calculator-grid {
    display: grid;
    justify-content: center;
    align-content: center;
    min-height: 100vh;
    grid-template-columns: repeat(4, 100px);
    grid-template-rows: minmax(120px, auto) repeat(5,100px); 
}
.calculator-grid > button{
    cursor: pointer;
    font-size: 2rem;
    outline: none;
    border: 1px solid white;
    background-color: rgba(255,255,255,0.6);
}
.calculator-grid > button:hover{
    background-color:  rgba(255,255,255,0.9);;
}

.span-two{
    grid-column: span 2;
}
.output{
    grid-column: 1 / -1;
    background-color: rgba(0, 0, 0, 0.759);
    display: flex;
    align-items: flex-end;
    justify-content: space-around;
    flex-direction: column;
    padding: 10px;
    word-wrap: break-word;
    word-break: break-all;
}
.output .previous-operand{
    color: rgba(255, 255, 255, 0.642);
    font-size: 1.5rem;
}
.output .current-operand{
    color: rgba(255, 255, 255, 0.801);
    font-size: 2.5rem;
}