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