JSFiddle - React, Tailwind, and code Playground

HTML

<div id="verticalScroller">
    <div>1 Lorem ipsum dolor sit</div>
    <div>2 Lorem ipsum dolor sit</div>
    <div>3 Lorem ipsum dolor sit</div>
    <div>4 Lorem ipsum dolor sit</div>
</div>

CSS

#verticalScroller {
    position: absolute;
    width:520px;
    height: 180px;
    border: 1px solid red;
    overflow: hidden;
}

#verticalScroller > div{
    /*position:absolute;*/
    width:50px;
    height:50px;
    border: 1px solid blue;
    overflow:hidden;
    float: left;
}

JavaScript

window.clients = function($elem) {
    var left = parseInt($elem.css("left"));
    var $cp = $("#clients .client");
    var temp = -1 * $cp.width();
    var guarda = [];

    $cp.each(function () {
        quantos.push($(this).width());
    });

    var quantos = guarda.length();

    if(left < temp) {
        left = $("#clients").width();
        $elem.css("left", left);
    }
    $elem.animate({ left: (parseInt(left)-230) }, 1000, "linear", function () {
        window.clients($(this));
    });
};

$(function () {
    $(document).ready(function() {
        var i = 0;
        $("#clients .client").each(function () {
          $(this).css("left", i);
          i += 230;
          window.clients($(this));
      });
        var totalinnerdivwidth = 0;
        $( "#verticalScroller" ).find( "div" ).each(function () {
            alert($(this).width());
             totalinnerdivwidth += $(this).width();
             });
        alert(totalinnerdivwidth);
    });

    $(".client").hover( function () {
        $(this).children("h3").stop().fadeIn("fast");
    }, function () {
        $(this).children("h3").stop().fadeOut("fast");
    });
    
});