theme : twenty eleven child theme
page where you find the sidebar : http://webdesign.igorlaszlo.com/tutoriels-astuces-composants/
i tried all of those solutions : http://wpbtips.wordpress.com/2012/05/19/sidebar-at-the-bottom-and-related-issues/#comment-52104 - it did not help.
probably it has moved today when i changed the style.css... i changed the web site width structure. before, the page, primary, content, secondary were in % and i fixed them in px because i do not like when the page is resized and some elements resize but some elements move, so the page becomes massy...
can someone look at my css what wrong is ?