JSFiddle - React, Tailwind, and code Playground

HTML

<div id="project_container">
    <div class="project_box"></div>
     <div class="project_box"></div>
     <div class="project_box"></div>
     <div class="project_box"></div>
     <div class="project_box"></div>

</div>

CSS

.project_box {
    display: none;
    width:50px;
    height:50px;
    background:blue;
    margin-bottom:10px;
}

JavaScript

$(function () {
    function animate() {
        $('.project_box:not(.completed):first')
        .animate(1500, function () {
            $(this).addClass('completed');
            animate({marginLeft: '50px'},1000);
        });
    }
    
    show();
});