styles-dark.css

@media (prefers-color-scheme: dark) {
    body {
        background-color: #333;
        color: #CCC;
    }

    .svg {
        background-color: black;
    }

    .svg-aux-circle {
        stroke: #888888;
        stroke-width: 0.5;
    }

    .svg-aux-line {
        stroke: #888888;
        stroke-width: 0.5;
    }

    .svg-pointer-line {
        stroke: #0088FF;
    }

    .svg-scale-text {
        fill: #888;
    }

    .svg-scale-circle-outer {
        stroke: #333;
        stroke-width: 0.5;
    }

    .svg-scale-circle-middle {
        stroke: #111;
        stroke-width: 20;
    }

    .svg-scale-circle-inner {
        stroke: #222;
        stroke-width: 0.5;
    }

    .info img, .sample {
        border: solid 1px #666;
        border-radius: 5px;
        box-shadow: 1px 1px 10px #111;
    }
    a {
        color: #08F;
    }
}