class Middleman::CoreExtensions::DefaultHelpers

def page_classes
  path = current_path.dup
  path << index_file if path.end_with?('/')
  path = ::Middleman::Util.strip_leading_slash(path)
  classes = []
  parts = path.split('.').first.split('/')
  parts.each_with_index { |path, i| classes << parts.first(i+1).join('_') }
  classes.join(' ')
end