function generateDedupedBaseCSS(usedTagNames) {
  const groups = new Map();

  for (let tagName of usedTagNames) {
    const styles = defaultStylesCache.get(tagName);
    if (!styles) continue;

    // Creamos la "firma" del bloque CSS para comparar
    const key = Object.entries(styles)
      .map(([k, v]) => `${k}:${v};`)
      .sort()
      .join('');

    // Agrupamos por firma
    if (!groups.has(key)) {
      groups.set(key, []);
    }
    groups.get(key).push(tagName);
  }

  // Ahora generamos el CSS optimizado
  let css = '';
  for (let [styleBlock, tagList] of groups.entries()) {
    css += `${tagList.join(',')} { ${styleBlock} }\n`;
  }

  return css;
}
Generates deduplicated base CSS for the given tag names.

@param {string[]} usedTagNames - Array of tag names
@returns {string} CSS string