$(function(){
    
    $('#menuGauche').each(function(){
            var parent = $(this).parent();
            var dTop = $(this).offset().top;
            var elem = $(this);
            $(window).scroll(function(){
                    parent.css('position','relative');
                    elem.css('position','absolute');
                    if(scrollY()>dTop){
                        elem.stop().animate({top:scrollY()-parent.offset().top+20},500);
                    }else{
                        elem.stop().animate({top:dTop-parent.offset().top},500)
                    }
            });
            if(scrollY()>dTop){
                elem.stop().animate({top:scrollY()-parent.offset().top+20},500);
            }
    });
    
});


/* Return the position of the top */

function scrollY() {
		scrOfY = 0;
		if( typeof( window.pageYOffset ) == 'number' ) {
			// Netscape compliant
			scrOfY = window.pageYOffset;
		} else if( document.body && ( document.body.scrollTop ) ) {
			// DOM compliant
			scrOfY = document.body.scrollTop;
		} else if( document.documentElement && ( document.documentElement.scrollTop ) ) {
			// IE6 standards compliant mode
			scrOfY = document.documentElement.scrollTop;
		}
		return scrOfY;
}