JSFiddle - React, Tailwind, and code Playground

HTML

<ul id="list">
    <li>Item 1</li>
    <li>Item 2</li>
    <li>Item 3</li>
    <li>Item 4</li>
</ul>

CSS

#list {
    width: 800px;
}

li {
    display: inline-block;
    float:left;
}

JavaScript

var evenWidth = $("#list").width()/$("#list li").size();
$("#list li").css("width", evenWidth);