public function countSelectors($css = null)
	{
		$count = 0;
		if ($css !== null && $this->css !== $css) {
			$this->css = $css;
			$this->parsedCss = $this->splitIntoBlocks($this->css);
		}
		foreach ($this->parsedCss as $rules) {
			$count += $rules['count'];
		}

		return $count;
	}