original_string: public function css( $cssClasses )
      {
          if ( ! $cssClasses )
          {
              return $this;
          }
  
          $cssClasses = explode( ' ', $cssClasses );
  
          foreach ( $cssClasses as $cssClass )
          {
              if ( $cssClass && false === in_array( $cssClass, $this->cssClasses ) )
              {
                  $this->cssClasses[] = $cssClass;
              }
          }
  
          return $this;
      }
code: public function css( $cssClasses )
      {
          if ( ! $cssClasses )
          {
              return $this;
          }
  
          $cssClasses = explode( ' ', $cssClasses );
  
          foreach ( $cssClasses as $cssClass )
          {
              if ( $cssClass && false === in_array( $cssClass, $this->cssClasses ) )
              {
                  $this->cssClasses[] = $cssClass;
              }
          }
  
          return $this;
      }
code_tokens: public function css ( $ cssClasses ) { if ( ! $ cssClasses ) { return $ this ; } $ cssClasses = explode ( ' ' , $ cssClasses ) ; foreach ( $ cssClasses as $ cssClass ) { if ( $ cssClass && false === in_array ( $ cssClass , $ this -> cssClasses ) ) { $ this -> cssClasses [ ] = $ cssClass ; } } return $ this ; }
docstring: Add a CSS class to the element. Multiple classes can be passed as a space-separated string.
  
  @param $cssClasses
  
  @return $this
docstring_tokens: Add a CSS class to the element . Multiple classes can be passed as a space - separated string .