I FOUND THE SOLUTION FOR MULTILANGUAGE FREE ON SQUARESPACE
Hello Every one! After many hours of works, i finelly sucess a good version of multinlingue website. Squarespace offer a very cheap solution. You can also subscribe on website to manage your translation but it cost money.
You can have a look on my website : link text
I do that only with javascript and its not complicate at all. If anyone need help, feeel free to ask.