class Kramdown::Converter::Kramdown

def convert_thead(el, opts)
  rows = inner(el, opts)
  if opts[:alignment].all? {|a| a == :default}
    "#{rows}|" << "-"*10 << "\n"
  else
    "#{rows}| " << opts[:alignment].map do |a|
      case a
      when :left then ":-"
      when :right then "-:"
      when :center then ":-:"
      when :default then "-"
      end
    end.join(' ') << "\n"
  end
end