$(document).ready(function(){
    
    // Preload images.
    var images = [
        'button-Home-over',
        'button-Why-XCAVATE-over',
        'button-Services-Over',
        'button-Career-Comm-Over',
        'button-Contact-Over',
    ];
    $.each(images, function(i, image){
        $('<img/>')[0].src = '/siteImages/' + image + '.gif';
    });
    
    // Attach hover events.
    $('#top-nav > ul > li')
        .mouseover(function(event){
            $(event.target).parents('#top-nav > ul > li').addClass('over');
        }).mouseleave(function(event){
            $(event.target).parents('#top-nav > ul > li').removeClass('over');
        });
});