body {
    background: #0f0a0a;
    height: 100vh;
    margin: 0px;
    overflow: hidden;
    -webkit-touch-callout: none; /* iOS Safari */
    -webkit-user-select: none; /* Safari */
     -khtml-user-select: none; /* Konqueror HTML */
       -moz-user-select: none; /* Old versions of Firefox */
        -ms-user-select: none; /* Internet Explorer/Edge */
            user-select: none; /* Non-prefixed version, currently
                                  supported by Chrome, Edge, Opera and Firefox */
}

div {
    font-family:Courier;
    color: #f4f0ed;
    font-size: 48px;
}

.buttons {
    display: grid;
    grid-template-columns: auto auto auto;
    grid-template-rows: auto auto auto auto;
    width: 99%;
    height: 61.8%;
    position: absolute;
    bottom: 0;
    padding: 2px;
}

.button {
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 48px;
    background: #42403e;
    margin: 2px;
    border: solid 2px #d4d0cd80;
    border-radius: 5px;
}

.null {
    grid-column-start: 1;
    grid-column-end: 3;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 48px;
    margin: 2px;
    border: solid 2px #d4d0cd80;
    border-radius: 5px;
}

.grey-bg {
    background: #42403e;
}

.yellow-bg {
    background: #cbbc73;
}

.grey-bg:active {
    background: #d3cfcc;
    color: #42403e;
}

.yellow-bg:active {
    background: #d3cfcc;
    color: #42403e;
}

.display {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-evenly;
    align-items: center;
    height: 23.2%;
    margin-top: 16px;
}

.input {
}

.output {
    font-size: 54px;
}

.history {
    min-width: 50%;
    font-size: 36px;
    color: #f4f0ed54;
}

.color-light {
    color: #f4f0ed;
}

.color-dark {
    color: #f4f0ed54;
}