* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    background-color: #f7f7f7;
}

.calculator {
    width: 18.75rem;
    background-color: #464646;
    border-radius: .625rem;
    box-shadow: 0px 4px 1px #00000040;
    font-family: 'Helvetica Neue', 'sans-serif';
    overflow: hidden;
}

.result {
    height: 4.688rem;
    padding: 1.25rem;
    text-align: right;
    color: #ffff;
    font-size: 2.5rem;
}

.buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1px;


    & button {
        display: flex;
        justify-content: center;
        align-items: center;
        width: 100%;
        height: 3.75rem;
        color: #fff;
        font-size: 1.5rem;
        font-weight: bold;
        border: none;
        outline: none;
        cursor: pointer;

    }


}

.button-zero {
    grid-column: span 2;
}

.bg-gray {
    background-color: #585858;
}

.bg-light-gray {
    background-color: #747474;
}

button:active {
    opacity: 0.9;
}

.bg-orange {
    background-color: #f2a43b;
}