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

body{
    padding: 0;
    margin:0;
    background: linear-gradient(to right,#00AAFF,#00FF6C);

}
 
.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 );

}
button{
    cursor: pointer;
    font-size:2rem;
    border:1px solid white;
    outline: none;
    background-color:rgba(255,255,255,.75);
}
.calculator-grid button:hover {
    background-color:rgba(255,255,255,.90);

}

.span-two{
    grid-column:span 2;
    color:green; 
}
.delete{
    color:red;
}

.op{
    color:orangered;
}

.eq{
    background-color: orangered;
    color: #000;
}

.output{
    grid-column: 1/-1; 
    background-color: rgba(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;
}

.output .previous-operand{
    color:rgba(255,255,255,.75);
    font-size:1.5rem;
}

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

.calculator-grid button .span-two {
    background-color: #000;
}