fullPage.js vertical navigation arrows

HTML

<script src="https://rawgit.com/alvarotrigo/fullPage.js/master/jquery.fullPage.js"></script>
<link rel="stylesheet" href="https://rawgit.com/jackmu95/fullPage.js/master/jquery.fullPage.css">
<div id="fullpage">
    <div id="section1" class="section">
        <h1>Sessão 1</h1>
    </div>

    <div id="section2" class="section">
        <h1>Sessão 2</h1>
        <p>Sessão onde o evento acontece</p>
        <button>Botão</button>
    </div>

    <div id="section3" class="section">
        <h1>Sessão 3</h1>
    </div>
</div>
<div id="modal">
    <div class="fundo"></div>
    <div class="modal-content">
        <div class="fundo_close"></div>
        <div class="item">Item 1</div>
        <div class="item">Item 2</div>
        <div class="item">Item 3</div>
    </div>
</div>

CSS

body,html{padding:0;margin:0;}
/* Section styles */
.section{text-align: center;}
.section h1,.section p {color: #333333;margin: 0;}
/* Janela Modal */
#modal{display:none;position:fixed;width:100%;height:100%;top:0;left:0;z-index:101;}
.fundo{background:rgba(0,0,0,.8);width:100%;height:100%;top:0;left:0;position:absolute}
.fundo_close{width:100%;height:100%;top:0;left:0;position:absolute}
.modal-content{width:100%;height:100%;top:0;left:0;position:absolute;}
.item{float:left;position:relative;width:100%;height:50px;margin:15px;background:#fff;z-index:1;}

JavaScript

$(function() {
    // Initialize fullPage
    $('#fullpage').fullpage({
        //Scrolling
        css3: true,
        scrollingSpeed: 1400,
        autoScrolling: false,
        fitToSection: false,
        scrollBar: false,
        easing: 'easeInOutCubic',
        easingcss3: 'ease',
        loopBottom: false,
        loopTop: false,
        loopHorizontal: true,
        continuousVertical: false,
        normalScrollElements: '#element1, .element2',
        scrollOverflow: true,
        touchSensitivity: 15,
        normalScrollElementTouchThreshold: 5,
        
        //Navigation
        navigation: true,
        navigationTooltips: ['First section', 'Second section', 'Third section'],
        sectionsColor: ['#f1c40f', '#e67e22', '#c0392b'],
        onLeave: function(index, nextIndex, direction) {
            // Remove the inactive class from all arrows
            $('#fp-nav > span').removeClass('inactive');

            // Add inactive class if needed
            if (nextIndex == 1) {
                $('#fp-nav > span.prev').addClass('inactive');
            } else if (nextIndex == $('.fp-section').length) {
                $('#fp-nav > span.next').addClass('inactive');
            }
        }
    });

    // Add previous and next arrows to the fullPage navigation
    $('#fp-nav').prepend('<span class="prev inactive">&#8593;</span>')
            .append('<span class="next">&#8595;</span>');

    // Re-center the fullPage navigation
    $('#fp-nav').css({ 'margin-top': '-' + ($('#fp-nav').height() / 2) + 'px' });

    // Add actions to the arrows
    $('#fp-nav').find('span.prev, span.next').on('click', function() {
        if ($(this).hasClass('prev')) {
            $.fn.fullpage.moveSectionUp();
        } else {
            $.fn.fullpage.moveSectionDown();
        }
    });
});
// Abre Janela Modal
$("button").click(function(){
    $("#modal").show();
    //Pausa a Rolagem do conteúdo atrás da modal
    $("body").stop().on({
            'mousewheel':...