public static function parse_css_rules( array $rules ) {

		ob_start();

		foreach ( $rules as $rule => $properties ) {

			printf(
				"%s {\n",
				implode( ",\n", array_map( 'trim', explode( ',', $rule ) ) )
			);

			foreach ( $properties as $property => $value ) {

				printf( "\t%s: %s;\n", $property, $value );

			}

			echo "}\n";

		}

		return ob_get_clean();

	}