html {
    background: #212121;
}

canvas {
    position: absolute;
    left: 0px;
    top: 0px;'
}

.btn {
    border-color: white;
    background-color: #212121;
    color: white;
    box-shadow: 0px 0px 2em black inset;
}

.btn.active {
    border-color: grey;
    background-color: white;
    color: black;
    box-shadow: 0px 0px 0.5em grey;
}

.underline {
    text-decoration: underline;
}

.transparent_btn {
    background: transparent;
    border: none !important;
    font-size:0;
    width: 2vw;
    height: 2vw;
}