JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <ul id="animals">
        <li>Dogs</li>
        <li>Cats</li>
        <li>Lions</li>
        <li>Tigers</li>
        <li>Zebras</li>
        <li>Giraffes</li>
        <li>Bears</li>
        <li>Hippopotamuses</li>
        <li>Antelopes</li>
        <li>Unicorns</li>
        <li>Seagulls</li>
        <li>Monkey</li>
        <li>Headhog</li>
        <li>Chicken</li>
        <li>Rabbit</li>
        <li>Gorilla</li>
    </ul>
</div>

CSS

div { width: 300px; }
ul li { float: left; border-right: 1px solid black; padding: 0 .5em; }
ul li:last-child { border: 0; }

JavaScript

var maxWidth = 300, // Your div max-width
    totalWidth = 0;
$('#animals li').each(function(){
    var currentWidth = $(this).outerWidth(),
        nextWidth = $(this).next().outerWidth();
    totalWidth += currentWidth;
    if ( (totalWidth + nextWidth) > maxWidth ) { 
        $(this).css('border', 'none');
        totalWidth = 0;
    }
});