@atlaskit/adf-schema/dist/es2019/utils/rgb-to-hex.js

Shared package that contains the ADF-schema (json) and ProseMirror node/mark specs

// eslint-disable-line import/no-namespace

export function rgbToHex(value) {
  const matches = value.match(/(0?\.?\d{1,3})%?\b/gu);
  if (matches && matches.length >= 3) {
    const [red, green, blue] = matches.map(Number);
    return '#' + (blue | green << 8 | red << 16 | 1 << 24).toString(16).slice(1);
  }
  return null;
}