Plesk Sitebuilder - use of Markup Validation Tool

Dear Sir/ Madam, 



Is it possible to use the Markup Validation tool for my website which I built with Plesk?


I used a Plesk Sitebuilder pre fixed stylesheet, so the possibilities to change the markup are little.



My website url is: http://www.nieuwekinderwagen.nl/


Thanks' in advance for your reply.


Kind regards, 




Maarten de Wilde