public static function clear($atts, $content = null)
 {
     extract(shortcode_atts(array('class' => '', 'gap' => 0), $atts));
     $before = $attributes = '';
     if (self::$columnsCount > 0) {
         self::$columnsCount = self::$columnsOffset = 0;
         $before = '</div>';
     }
     if ($gap > 0) {
         if ($gap == 20) {
             $class .= ' offsetTopS';
         } else {
             if ($gap == 60) {
                 $class .= ' offsetTop';
             } else {
                 if ($gap == 80) {
                     $class .= ' offsetTopL';
                 } else {
                     if ($gap == 120) {
                         $class .= ' offsetTopX';
                     } else {
                         $attributes = ' style="padding-top: ' . intval($gap) . 'px;"';
                     }
                 }
             }
         }
     }
     return $before . '<div class="clear' . (!empty($class) ? ' ' . trim(esc_attr($class)) : '') . '"' . $attributes . '></div>';
 }