Шаблон:ColoredTextFrame/styles.css

.сolored-frame-text {
    --perceived-lightness: calc( ((var(--label-r) * 0.2126) + (var(--label-g) * 0.7152) + (var(--label-b) * 0.0722)) / 255 );
    --lightness-switch: max(0, min(calc((1/(var(--lightness-threshold) - var(--perceived-lightness)))), 1));
    
    --lighten-by: calc(((var(--lightness-threshold) - var(--perceived-lightness)) * 100) * var(--lightness-switch));
    
    --label-r-calc: calc(var(--label-r) + var(--lighten-by));
    --label-g-calc: calc(var(--label-g) + var(--lighten-by));
    --label-b-calc: calc(var(--label-b) + var(--lighten-by));
}

.сolored-frame-text {
    display: block;
    padding: 6px 8px;
    border: 1px solid transparent;
    border-radius: 0.5em;

    background: rgba(var(--label-r), var(--label-g), var(--label-b), var(--background-alpha));
    border-color: rgba(var(--label-r), var(--label-g), var(--label-b), var(--border-alpha));
}

.сolored-frame-text__header {
    font-size: 15px;
    font-weight: bold;
    font-family: "noto sans";
    margin-bottom: 4px;
    color: rgba(var(--label-r-calc), var(--label-g-calc), var(--label-b-calc), 1);
}

.сolored-frame-text__content {
    color: lightgray;
}