* {
    box-sizing: border-box;
    font-family: monospace;
    font-size: 36px;
    padding: 0;
    margin: 0;
}

body {
    display:flex;
    flex-direction: column;
    align-items: center;
}

#gridContainer {

    box-sizing: border-box;
    margin-top: 30px;
    display: grid;
    grid-template-columns: 1;
    grid-template-rows: 2;
    width: fit-content;
    box-shadow: rgba(50, 50, 93, 0.25) 0px 50px 100px -20px, rgba(0, 0, 0, 0.3) 0px 30px 60px -30px, rgba(10, 37, 64, 0.35) 0px -2px 6px 0px inset;
    background-color: rgba(161, 161, 161, 0.596);
    border-radius: 10px;
    outline: solid black 2px;

}

#buttons {
    display: grid;
    background-color: rgba(161, 161, 161, 0.596);
    grid-template-columns: repeat(4, 60px);
    grid-template-rows: repeat(5, 60px);
    
}

button {
    font-size: 16px;
    
    border: solid black 1px;
    border-radius: 8px;
}

button:active {
    background-color: rgb(146, 146, 90);
}

#calculatorDisplay {
    margin-top: 16px;
    border-radius: 8px;
    width: 240px;
    height: 60px;
    text-align: right;
    background-color: black;
    color: green;
    margin-bottom: 20px;
}

[id='0'] {
    grid-column-start: 1;
    grid-column-end: 3;
    grid-row: 5;

}

[id='clear'] {
    background-color: orangered;

}

[id='equals'] {
    background-color: rgba(161, 161, 161, 0.596);
    color: antiquewhite;

}

.operator {
    background-color: rgba(161, 161, 161, 0.87);
    color: antiquewhite;
}

.footer, a{
    margin-top: 30px;
    flex: 1;
    font-size: 12px;
    color: black;
}