body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}

#container {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-gap: 5px;
    max-width: 300px;

    border: 3px solid black;
    background-color: lightblue;
    padding: 1rem;
}

.key {
    width: 50px;
    height: 50px;
    font-size: 20px;
}

.calculator_output {
    grid-column: span 4;
    height: 50px;
    font-size: 24px;

    text-align: right;
}

.calculator_history {
    grid-column: span 4;
    height: 20px;
    font-size: 12px;

    text-align: right;
}

.key_enter {
    background-color: rgb(248, 169, 169);
}