content: on run argv
    set _output to ""
    set operation to item 1 of argv
    set px to item 2 of argv
    tell application "Google Chrome"
      tell active tab of window 1
        if ("down" = operation) then
          execute javascript "window.scrollBy(0,"&px&");"
        else if ("up" = operation) then
          execute javascript "window.scrollBy(0,-"&px&");"
        end if
      end tell
    end tell
    return _output
  end run
  