var ui = {
	initialize: function(){
		this.imgs = new Array('btn_contact','btn_cursus');
		
		this.preloadImages();
		
		$$('.button').each(function(el){
			Event.observe(el, 'mouseover', this.flip.bindAsEventListener(this));
			Event.observe(el, 'mouseout', this.flip.bindAsEventListener(this));
		}.bind(this));
	},
	
	preloadImages: function() {
		var imgs_loaded = new Array();
		for(i = 0; i< this.imgs.length; i++) {
			imgs_loaded[i] = new Image();
			imgs_loaded[i].src = '/media/landing/' + this.imgs[i] + '-over.gif';
		}
	},
	
	flip: function(e) {
		if(e.element().src.indexOf('btn_contact.gif') != -1)
			e.element().src='/media/landing/btn_contact-over.gif';
		else if(e.element().src.indexOf('btn_contact-over.gif') != -1)
			e.element().src='/media/landing/btn_contact.gif';
		else if(e.element().src.indexOf('btn_cursus.gif') != -1)
			e.element().src='/media/landing/btn_cursus-over.gif';
		else if(e.element().src.indexOf('btn_cursus-over.gif') != -1)
			e.element().src='/media/landing/btn_cursus.gif';
	}
}