JSFiddle - React, Tailwind, and code Playground

HTML

<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box"></div>
<div class="box" id="the-box">This BOX</div>
<div class="box"></div>
<div class="box"></div>

CSS

.box {
	border:2px solid black;
	height: 400px; 
	width: 200px;
	margin: 0 auto;
	margin-top:10px;
}

JavaScript

// document ready
$(function () {
    
    // define the isOnScreen plugin from http://jsfiddle.net/moagrius/wN7ah/
    $.fn.isOnScreen = function() {
        var win = $(window);
        
        var viewport = {
            top : win.scrollTop(),
            left : win.scrollLeft(),
            right: win.scrollLeft() + win.width(),
            bottom: win.scrollTop() + win.height()
        };
        
        var bounds = this.offset();
        bounds.right = bounds.left + this.outerWidth();
        bounds.bottom = bounds.top + this.outerHeight();
        
        return (!(viewport.right < bounds.left || viewport.left > bounds.right || viewport.bottom < bounds.top ||     viewport.top > bounds.bottom)); 
    };
       
    // define throttling function for use in scroll event listener
    // ref: http://blogorama.nerdworks.in/javascriptfunctionthrottlingan/
    function throttle(delay, callback) {
        var previousCall = new Date().getTime();
        return function() {
            var time = new Date().getTime();
            if ((time - previousCall) >= delay) {
                previousCall = time;
                callback.apply(null, arguments);
            }
        };
    }
    
    // set up an event to listen for window scroll 4 times a second
    $(window).on('scroll', throttle( 250, function () {
        
        // if #the-box is visible the call init functions and disable window scroll
        // event listener, as you only want to initialise the lightbox once
        if ( $("#the-box").isOnScreen() ) {
            
            // for demo purposes
            alert('init');
            
            // call your init functions here
            //getThemenCount();
            //moveThemenAnimate();
            
            // turn off scroll listener
            $(window).off('scroll');
        }
    }));
});