public static function getColumnsConfiguration(array $data)
	{
		$config = array();
		$lastColumns = null;

		foreach (array('large', 'medium', 'small') as $media) {

			$columns = isset($data['rs_columns_' . $media])
				? $data['rs_columns_' . $media]
				: null;
			if (!$columns) {
				$columns = $lastColumns ?: '2';
			}
			$lastColumns = $columns;

			$columns = array_map(function($value) {
				return (int)$value ?: 1;
			}, explode('-', $columns));

			if (count($columns) === 1 && $columns[0] > 1) {
				$columns = array_fill(0, (int)$columns[0], '1');
			}

			$columnsTotal = array_reduce($columns, function($a, $b) {
				return $a + $b;
			});
			$classes = array();
			foreach ($columns as $key => $column) {
				$classes[] = array('-' . $media . '-col-' . $columnsTotal . '-' . $column);
			}
			$classes[0][] = '-' . $media . '-first';
			$classes[count($classes) - 1][] = '-' . $media . '-last';
			$config[$media] = $classes;

		}

		return $config;
	}