/**
* Sets the background color.
*
* @param string $color One of the color constants.
*
* @return static The current instance.
*/
public function bg($color)
{
Assert::nullOrOneOf($color, self::$colors, 'The color must be null or one of the Style::* color constants. Got: "%s"');
$this->bgColor = $color;
return $this;
}
