var EICProduit = {

	start: function(){
	  if( $('nav')) {
	    setInterval( function() { EICProduit.moveNav('nav', 'page');	}, 800);
	  }
	},
	
	moveNav: function(nav, page) {
    var effectNav = new Fx.Morph( nav, {'duration': 500, 'transition': Fx.Transitions.circOut}) ;
    var marginTop = $(nav).getStyle('margin-top');
    var posTo = document.documentElement.scrollTop - 187 /* bannière */;
    if( posTo>0) {
      var navHeight = $(nav).getCoordinates().height;
      var pageHeight = $(page).getCoordinates().height;
      if(navHeight>pageHeight) {
        posTo = 0;
      } else {
        if(( posTo+navHeight)>( pageHeight-0)) posTo = pageHeight - navHeight - 0;
      }
    } else
      posTo = 0;
    effectNav.start({ 'margin-top' : [marginTop, posTo] });
	}
};

window.addEvent('domready', EICProduit.start);