//http://davidwalsh.name/dw-content/snook-animation.php
//<script type="text/javascript" src="http://meinedomain.com/dateien/jsfiles/walsh_nav.js"></script>



window.addEvent('domready', function() {
  /* example a:  top down */
  $$('#a a').each(function(el) {
    //fx
    var fx = new Fx.Tween(el,{
      duration: 500,
      link: 'cancel'
    });
    
    //css & events
    el.setStyle('background-position','-20px 37px').addEvents({
      'mouseenter': function(e) {
        e.stop();
        fx.start('background-position','-20px 121px');
      },
      'mouseleave': function(e) {
        e.stop();
        fx.start('background-position','-20px 37px');
      }
    });
  });
  
  /* example b:  right left */
  $$('#mainnav a').each(function(el) {
    //css
    var reset = false;
    var fx = new Fx.Tween(el,{
      duration: 500,
      link: 'cancel',
      onComplete:function() {
        if(reset) {
          el.setStyle('background-position','0 0');
        }
      }
    });
    //events
    el.setStyle('background-position','0 0').addEvents({
      'mouseenter': function(e) {
        e.stop();
        fx.start('background-position','240px -2px');
        reset = false;
      },
      'mouseleave': function(e) {
        reset = true;
        fx.start('background-position','480 -2px');
      }
    });
  });
  
});