Derives the map colours from a stylesheet — a site's CSS, a design system's tokens —
by reading the colours it paints with (cssColors) and assigning them roles with
deriveMapColors.
With mode: 'auto', the default, the map is light or dark as the page is: its background on
:root, html or body, or else the grey most rules fill with, and light when neither resolves.
Needs no DOM.
RangeError when the stylesheet paints with no opaque colour.
Example
// A File from an <input type="file" accept=".css">, or CSS a server fetched styling.setMapColors(deriveMapColorsFromCss(awaitfileInput.files[0].text()));
Derives the map colours from a stylesheet — a site's CSS, a design system's tokens — by reading the colours it paints with (cssColors) and assigning them roles with deriveMapColors.
With
mode: 'auto', the default, the map is light or dark as the page is: its background on:root,htmlorbody, or else the grey most rules fill with, and light when neither resolves. Needs no DOM.