var initializeApplication = function(){

    $$('div#pub-yp-list-hazard-container-div div.content').each(function(element){
        element.observe('mouseover', function(event){
            var obj = Event.findElement(event, 'div.content');
            obj.addClassName('selected-content');
        });
        element.observe('mouseout', function(event){
            var obj = Event.findElement(event, 'div.content');
            if( obj.hasClassName('selected-content') ){
                obj.removeClassName('selected-content');
            }
        });
    });
}

Event.observe(window, 'load', initializeApplication);